Ophthalmic lens supply system and related methods

ABSTRACT

A system for the supply of ophthalmic lenses and related methods for providing ophthalmic lenses for enhanced experience based on right-handedness and left-handedness.

RELATED APPLICATIONS

This application is a U.S. National Phase Application under 35 USC 371of International Application PCT/EP2013/063608 filed Jun. 28, 2013.

This application claims the priority of European application No.12305772.1 filed Jun. 29, 2012, and 13305191.2 filed Feb. 20, 2013, theentire content of both of which are hereby incorporated by reference.

FIELD OF THE INVENTION

The invention relates to ophthalmic lenses and spectacles for enhancedexperience due to right handedness or lefthandedness.

BACKGROUND OF THE INVENTION

A wearer may be prescribed a positive or negative optical powercorrection. For presbyopic wearers, the value of the power correction isdifferent for far-vision and near-vision, due to the difficulties ofaccommodation in near-vision. Ophthalmic lenses suitable for presbyopicwearers are multifocal lenses, the most suitable being progressivemultifocal lenses.

The inventors have found that right-handed persons and left-handedpersons behave quite differently when performing certain tasks, whetherinvolving near-vision, intermediate-vision and/or far-vision. However,current lens designs do not include handedness as a design factor,whereas such factor impacts on wearer visual comfort.

SUMMARY OF THE INVENTION

One aspect of the present invention provides an ophthalmic lens supplysystem for providing an ophthalmic lens that takes into account thehandedness of the wearer for whom the lens is intended. Further, thepresent invention provides computer-implemented methods for thedetermination and the manufacture of an ophthalmic lens by taking intoaccount the handedness of the wearer for whom the lens is intended. Theinvention also provides related computer-program products.

Embodiments of the invention advantageously confer superior visualcomfort to the wearer, and may be customized for improved comfort fornear-vision and/or intermediate-vision and/or far-vision. Thus, improvedcomfort as a function of handedness may be further provided for specificwearer tasks and activities.

Further features and advantages of the invention will appear from thefollowing description of embodiments of the invention, given asnon-limiting examples, with reference to the accompanying drawingslisted hereunder.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1 to 3 show, diagrammatically, optical systems of eye and lens andray tracing from the center of rotation of the eye;

FIGS. 4 and 5 show referentials defined with respect to micro-markings,for a surface bearing micro-markings and for a surface not bearing themicro-markings respectively;

FIGS. 6 and 7 show field vision zones of a lens;

FIG. 8 shows an optical system of eyes and lenses when executing a nearvision task;

FIGS. 9 and 10 show envelopes of gaze directions corresponding to usefulzone when swept by the optical system of FIG. 8;

FIGS. 11 to 18 and 19 a to 22 a give optical characteristics for threeexamples of pair of progressive ophthalmic lenses according to theinvention;

FIG. 19 shows an illustration of the Cyclopean binocular system ofcoordinates that may be used to define ergoramas useful according to thepresent invention;

FIG. 20 shows an example of a handedness-specific ergorama usefulaccording to the present invention;

FIG. 21 illustrates inset determination according to the invention;

FIG. 22 shows optical characteristics of lenses obtainable by theinvention;

FIG. 23 illustrates schematically an exemplary ophthalmic lens supplysystem of the invention;

FIG. 24 illustrates schematically exemplary methods for determining anophthalmic lens in accordance with the invention.

It can be appreciated that elements in the figures are illustrated forsimplicity and clarity and have not necessarily been drawn to scale. Forexample, the dimensions of some of the elements in the figures may beexaggerated relatively to other elements to help improving theunderstanding of the embodiments of the present invention.

DEFINITIONS

The following definitions are provided to describe the presentinvention.

-   “Prescription data” are known in the art. Prescription data refers    to one or more data obtained for the wearer and indicating for each    eye a prescribed far vision mean refractive power P_(FV), and/or a    prescribed astigmatism value CYL_(FV) and/or a prescribed    astigmatism axis AXE_(FV) and/or a prescribed addition A suitable    for correcting the ametropia and/or presbyopia of each eye. The mean    refractive power P_(FV) is obtained by summing the half value of the    prescribed astigmatism value CYL_(FV) to the prescribed sphere value    SPH_(FV): P_(FV)=SPH_(FV)+CYL_(FV)/2. Then, the mean refractive    power for each eye for proximate (near) vision is obtained by    summing the prescribed addition A to the far vision mean refractive    power P_(FV) prescribed for the same eye: P_(NV)=P_(FV)+A. In the    case of a prescription for progressive lenses, prescription data    comprise wearer data indicating for each eye values for SPH_(FV),    CYL_(FV) and A.-   “Handedness” or “laterality” indicates the preference and/or the    propensity of an individual to use one hand or the other. This is    typically observed for a task such as writing, but is also reflected    in other activities. A handedness parameter H can be used to    describe the handedness of a subject.-   “Ophthalmic lenses” are known in the art. According to the    invention, the ophthalmic lens may be selected from progressive and    regressive lenses; monofocal, bifocal, or more generally multifocal    lenses. The lens may be for use in spectacles (eyeglasses), as    contact lenses or as intraocular implants. The lens may also be a    lens for information glasses, wherein the lens comprises means for    displaying information in front of the eye. The lens may be a    prescription or non-prescription lens. The lens may also be suitable    for sunglasses or not. Preferred lenses according to the invention    are progressive ophthalmic lenses, including progressive multifocal    ophthalmic lenses. All ophthalmic lenses obtainable according to the    invention may be paired so as to form a pair of lenses (left eye LE,    right eye RE).-   A “pair of lenses” intended for a wearer designates a pair of lenses    which are intended to be worn simultaneously by said wearer. Said    pair is intended to be fitted into a frame.-   A “gaze direction” can be identified by a couple of angle values    (α,β), wherein said angles values are measured with regard to    reference axes centered on the center of rotation of the eye (CRE).    More precisely, FIG. 1 represents a perspective view of such a    system illustrating parameters α and β used to define a gaze    direction. FIG. 2 is a view in the vertical plane parallel to the    antero-posterior axis of the wearer's head and passing through the    center of rotation of the eye in the case when the parameter β is    equal to 0. The center of rotation of the eye is labeled Q′. The    axis Q′F′, shown on FIG. 2 in a dot-dash line, is the horizontal    axis passing through the center of rotation of the eye and extending    in front of the wearer—that is the axis Q′F′ corresponding to the    primary gaze direction. This axis cuts the front surface of the lens    on a point called the fitting cross, which is present on lenses to    enable the positioning of lenses in a frame by an optician. The    fitting cross corresponds to a lowering angle α of 0° and an azimuth    angle β of 0°. The point of intersection of the rear surface of the    lens and the axis Q′F′ is the point O. O can be the fitting cross if    it is located on the rear surface. A vertex sphere, of center Q′,    and of radius q′, which is intercepting the rear surface of the lens    in a point of the horizontal axis. As examples, a value of radius q′    of 25.5 mm corresponds to a usual value and provides satisfying    results when wearing the lenses.    -   A given gaze direction represented by a solid line on FIG.        1—corresponds to a position of the eye in rotation around Q′ and        to a point J (see FIG. 2) of the vertex sphere; the angle β is        the angle formed between the axis Q′F′ and the projection of the        straight line Q′J on the horizontal plane comprising the axis        Q′F′; this angle appears on the scheme on FIG. 1. The angle α is        the angle formed between the axis Q′J and the projection of the        straight line Q′J on the horizontal plane comprising the axis        Q′F′; this angle appears on the scheme on FIGS. 1 and 2. A given        gaze view thus corresponds to a point J of the vertex sphere or        to a couple (α, β). The more the value of the lowering gaze        angle is positive, the more the gaze is lowering and the more        the value is negative, the more the gaze is rising.    -   In a given gaze direction, the image of a point M in the object        space, located at a given object distance, is formed between two        points S and T corresponding to minimum and maximum distances JS        and JT, which would be the sagittal and tangential local focal        lengths. The image of a point in the object space at infinity is        formed, at the point F′. The distance D corresponds to the rear        frontal plane of the lens.    -   On the lens, for each gaze direction (α, β), a refractive power        P_(α,β), a module of astigmatism Ast_(α,β) and an axis Axe_(α,β)        of this astigmatism, and a module of resulting (also called        residual or unwanted) astigmatism Asr_(α,β) are defined.-   “Ergorama” is a function associating to each gaze direction the    usual distance of an object point. Typically, in far vision    following the primary gaze direction, the object point is at    infinity. In near vision, following a gaze direction essentially    corresponding to an angle α of the order of 35° and to an angle β of    the order of 5° in absolute value towards the nasal side, the object    distance is of the order of 30 to 50 cm. For more details concerning    a possible definition of an ergorama, U.S. Pat. No. 6,318,859 may be    considered. This document describes an ergorama, its definition and    its modeling method. For a method of the invention, points may be at    infinity or not. Ergorama may be a function of the wearer's    ametropia. In the context of a unifocal lens, the ergorama may be    defined as a plane situated at infinity distance.    -   Using these elements, it is possible to define a wearer optical        power and astigmatism, in each gaze direction. An object point M        at an object distance given by the ergorama is considered for a        gaze direction (α,β). An object proximity ProxO is defined for        the point M on the corresponding light ray in the object space        as the inverse of the distance MJ between point M and point J of        the vertex sphere:

ProxO=1/MJ

-   -   This enables to calculate the object proximity within a thin        lens approximation for all points of the vertex sphere, which is        used for the determination of the ergorama. For a real lens, the        object proximity can be considered as the inverse of the        distance between the object point and the front surface of the        lens, on the corresponding light ray.    -   For the same gaze direction (α,β), the image of a point M having        a given object proximity is formed between two points S and T        which correspond respectively to minimal and maximal focal        distances (which would be sagittal and tangential focal        distances). The quantity Prox I is called image proximity of the        point M:

${{Prox}\; I} = {\frac{1}{2}( {\frac{1}{JT} + \frac{1}{JS}} )}$

-   -   The optical power is also called refractive power    -   By analogy with the case of a thin lens, it can therefore be        defined, for a given gaze direction and for a given object        proximity, i.e. for a point of the object space on the        corresponding light ray, an optical power Pui as the sum of the        image proximity and the object proximity.

Pui=ProxO+ProxI

-   -   With the same notations, an astigmatism Ast is defined for every        gaze direction and for a given object proximity as:

${Ast} = {{\frac{1}{JT} - \frac{1}{JS}}}$

-   -   This definition corresponds to the astigmatism of a ray beam        created by the lens.

FIG. 3 represents a perspective view of a configuration wherein theparameters α and β are non-zero. The effect of rotation of the eye canthus be illustrated by showing a fixed frame {x, y, z} and a frame{x_(m), y_(m), z_(m)} linked to the eye. Frame {x, y, z} has its originat the point Q′. The axis x is the axis Q′O and it is orientated fromthe lens towards the eye. The y axis is vertical and orientatedupwardly. The z axis is such that the frame {x, y, z} is orthonormal anddirect. The frame {x_(m), y_(m), z_(m)} is linked to the eye and itscenter is the point Q′. The x_(m) axis corresponds to the gaze directionJQ′. Thus, for a primary gaze direction, the two frames {x, y, z} and{x_(m), y_(m), z_(m)} are the same. It is known that the properties fora lens may be expressed in several different ways and notably in surfaceand optically. A surface characterization is thus equivalent to anoptical characterization. In the case of a blank, only a surfacecharacterization may be used. It has to be understood that an opticalcharacterization requires that the lens has been machined to thewearer's prescription. In contrast, in the case of an ophthalmic lens,the characterization may be of a surface or optical kind, bothcharacterizations enabling to describe the same object from twodifferent points of view. Whenever the characterization of the lens isof optical kind, it refers to the ergorama-eye-lens system describedabove. For simplicity, the term ‘lens’ is used in the description but ithas to be understood as the ‘ergorama-eye-lens system’. The value insurface terms can be expressed with relation to points. The points arelocated with the help of abscissa or ordinate in a frame as definedabove with respect to FIGS. 4 and 5.

-   -   The values in optic terms can be expressed for gaze directions.        Gaze directions are usually given by their degree of lowering        and azimuth in a frame whose origin is the center of rotation of        the eye. When the lens is mounted in front of the eye, a point        called the fitting cross is placed before the pupil or before        the eye rotation center Q′ of the eye for a primary gaze        direction. The primary gaze direction corresponds to the        situation where a wearer is looking straight ahead. In the        chosen frame, the fitting cross corresponds thus to a lowering        angle α of 0° and an azimuth angle β of 0° whatever surface of        the lens the fitting cross is positioned—rear surface or front        surface.    -   The above description made with reference to FIGS. 1-3 was given        for central vision. In peripheral vision, as the gaze direction        is fixed, the center of the pupil is considered instead of        center of rotation of the eye and peripheral ray directions are        considered instead of gaze directions. When peripheral vision is        considered, angle α and angle β correspond to ray directions        instead of gaze directions.    -   In the remainder of the description, terms like <<up>>,        <<bottom>>, <<horizontal>>, << vertical>>, <<above>>, <<below>>,        or other words indicating relative position may be used. These        terms are to be understood in the wearing conditions of the        lens. Notably, the “upper” part of the lens corresponds to a        negative lowering angle α<0° and the “lower” part of the lens        corresponds to a positive lowering angle α>0°. Similarly, the        “upper” part of the surface of a lens—or of a semi-finished lens        blank—corresponds to a positive value along the y axis, and        preferably to a value along the y axis superior to the y value        corresponding to the fitting cross and the “lower” part of the        surface of a lens—or of a semi-finished lens blank—corresponds        to a negative value along the y axis in the frame as defined        above with respect to FIGS. 4 and 5, and preferably to a value        along the y axis inferior to the y_value at the fitting cross.

-   The “meridian line” of a progressive lens may be defined as follows:    for each lowering of the view of an angle α=α₁ between the gaze    direction corresponding to the fitting cross and the bottom of the    lens, the gaze direction (α₁, β₁) is searched by ray tracing, in    order to be able to see clearly the object point located in the    median plane, at the distance determined by the ergorama. The median    plane is the median plane of the head, preferentially passing    through the base of the nose. This plane may also be passing through    the middle of right and left eye rotation centers.    -   Thus, all the gaze directions defined in that way form the        meridian line of the ergorama-eye-lens system. For        personalization purpose, postural data of the wearer, such as        angle and position of the head in the environment, might be        taken into account to determine the object position. For        instance, the object position might be positioned out of median        plane to model a wearer lateral shift in near vision.    -   The meridian line of the lens represents the locus of mean gaze        directions of a wearer when he is looking from far to near        visions.

-   The “surface meridian line” 32 of the lens is defined as follow:    each gaze direction (α, β) belonging to the meridian line of the    lens intersects the surface in a point (x, y). The surface meridian    line is the set of points corresponding to the gaze directions of    the meridian line of the lens.    -   As shown in FIG. 7, the surface meridian line 32, belonging for        example to the front surface of the lens, separates the lens in        a nasal area (N) and a temporal area (T). As expected, the nasal        area is the area of the lens which is between the meridian and        the nose of the wearer whereas the temporal area is the area        which is between the meridian and the temple of the wearer.

-   The “channel line” is defined for a progressive lens as the line    containing the gaze directions that corresponds to the minimum of    resulting astigmatism or the line located at almost equal distance    from two gaze directions through the lens respectively on the nasal    side and the temporal side, with same values for the lowering angle    and also same values for the resulting astigmatism. Usually, lens    manufacturers will match the meridian line of a progressive lens    with approximately the channel line. Each meridian line or each    channel line are contained in a vertical plane above the fitting    cross, and deflected towards the nasal side below the fitting cross.

-   The “meridian line” and the “channel line” of a unifocal lens are    defined as the vertical straight line passing through the optical    center of the lens.

-   The “off-centered zone” of a lens is defined as the zone containing    all the gaze directions comprised:    -   inside a zone centered on to the gaze direction corresponding to        gaze directions passing through the PRP and containing all gaze        directions (α, β) respecting the following inequality        (|a|²+|β|²)^(1/2)≦40°, and    -   outside a central optical zone; the central optical zone        comprising a meridian line (α₁, β₁), the central optical zone        being delimited on either side of the meridian line by gaze        directions whose azimuth angle is equal to β₁±5°.

-   The “nasal” and “temporal” sides of the lens are defined with    respect to the meridian line. The nasal (resp. temporal) side    corresponds to the set of gaze directions within the “off-centered    zone” and limited to the side of the nose (resp. temple) with    respect to the meridian line.

-   The “visual field zones” seen through a progressive lens are known    to the skilled person and are schematically illustrated in FIGS. 6    and 7. The lens comprises a far vision (distant vision) zone 26    located in the upper part of the lens, a near vision zone 28 located    in the lower part of the lens and an intermediate zone 30 situated    between the far vision zone 26 and the near vision zone 28. The lens    also has a surface meridian line 32 belonging for example to the    front surface and passing through the three zones and defining a    nasal side and a temporal side.

-   The “visual field zones” of a unifocal lens are defined as follows:    -   For a far-vision unifocal lens, namely a unifocal lens        prescribed and mounted for far vision correction, the far-vision        reference point corresponds to the optical center, the        near-vision reference point corresponds to the point used for        proximate vision, for example a point of coordinates NV (0, −15        mm), and the intermediate-vision reference point corresponds to        the point used for intermediate vision, for example a point of        coordinates IV (0, −7.5 mm), wherein the coordinates are        relative to a Cartesian system of reference coordinates (OC,        x,y) centered on the optical center OC of the lens localized on        the front surface and of axes x and y belonging to the        tangential plane to the front surface of the lens at OC, the x        axis being parallel to the terrestrial plane when the lens is        fitted into the frame and is worn by the wearer being in primary        gaze situation (x axis is parallel to the axis formed by the        micro-markings, if they are present; by analogy to a progressive        lens, see FIG. 4), the y axis being perpendicular to the x axis;    -   For a near-vision unifocal lens, namely a unifocal lens        prescribed and mounted for near vision correction, the        near-vision reference point corresponds to the optical center,        the intermediate-vision reference point may have coordinates of        (0, +7.5 mm) and the far-vision reference point may have        coordinates of (0, +15 mm) in the above defined Cartesian        system;    -   The far-vision, near-vision and intermediate-vision zones of a        unifocal lens are defined respectively as zones of the lens        surrounding the far-vision, near-vision and intermediate vision        reference points. Similar to FIG. 6, the limits of said zones        may be defined at intermediary distance between the reference        points.

-   A “proximate vision gaze direction” (α_(PV), β_(PV)) is defined for    a lens, and may be also defined for each lens of a pair, that is to    say a left proximate vision gaze direction (α_(PVL), β_(PVL)) for    the left-eye lens of the pair and a right proximate vision gaze    direction (α_(PVR), β_(PVR)) for the right-eye lens of the pair.    -   The proximate vision gaze direction belongs to the meridian        line.    -   Generally, for a progressive lens, the proximate vision gaze        direction, and thus α_(PV), is such that the corresponding        refractive power is comprised between the prescribed far vision        mean power P_(FV) for this lens plus 50% of the addition A        prescribed for this lens and the far vision mean power P_(FV)        prescribed for this lens plus 125% of the addition prescribed        for this lens.    -   Advantageously, the proximate vision gaze direction, and thus        α_(PV), is defined, for each lens of the pair, as the gaze        direction where the refracting power reaches the far vision mean        power P_(FV) prescribed for this lens plus 85% of the addition A        prescribed for this lens or as the gaze direction where the        refracting power reaches the far vision mean power P_(PV)        prescribed for this lens plus 100% of the addition A prescribed        for this lens

-   A “near-vision temporal half-width of refractive power” T_(P,nv) is    defined for the optical function of a progressive lens, as the    angular distance, at constant lowering angle α, between the    proximate vision gaze direction (α_(PV), β_(PV)) and a gaze    direction (α_(PV), β_(TP,nv)) on the temporal side of the lens where    the refractive power P_(αPV,βTP,nv) reaches the value of the    prescribed far vision mean power P_(PV) for the lens plus three    quarters of the prescribed addition A for the lens:

P _(αPV,βTP,nv) =P _(FV)+¾*A

-   A “near-vision nasal half-width of refractive power” N_(P,nv) is    defined for the optical function of a progressive lens, as the    angular distance, at constant lowering angle α, between the    proximate vision gaze direction (α_(PV), β_(PV)) and a gaze    direction (α_(PV), β_(NP)) on the nasal side of the lens where the    refractive power P_(αPV,βNP) reaches the value of the prescribed far    vision mean power P_(PV) for the lens plus three quarters of the    prescribed addition A for the lens:

P _(αPV,βNP,nv) =P _(FV)+¾*A

-   A “near-vision temporal half-width of module of resulting    astigmatism” T_(A,nv) is defined for the optical function of a    progressive lens, as the angular distance, at constant lowering    angle α, between the proximate vision gaze direction (α_(PV),    β_(PV)) and a gaze direction (α_(PV), P_(TA,nv)) on the temporal    side of the lens where the module of resulting astigmatism    Asr_(αPV,βTA,nv) reaches the value of one quarter of the prescribed    addition A for the lens:

Asr _(αPV,βTA,nv) =A/4

-   A “near-vision nasal half-width of module of resulting astigmatism”    N_(A,nv) is defined for the optical function of a progressive lens,    as the angular distance, at constant lowering angle α, between the    proximate vision gaze direction (α_(PV), β_(PV)) and a gaze    direction (α_(PV), β_(NA,nv)) on the nasal side of the lens where    the module of resulting astigmatism Asr_(αPV,βNA,nv) reaches the    value of one quarter of the prescribed addition A for the lens:

Asr _(αPV,βNA,nv) =A/4

-   A “near-vision temporal half-width of refractive power” T_(P,nv) is    defined for the optical function of a near-vision unifocal lens, as    the angular distance, at constant lowering angle α, between the    proximate vision gaze direction (α_(PV), β_(PV)) and a gaze    direction (α_(PV), β_(TP,nv)) on the temporal side of the lens where    the refractive power P_(αPV,βTP,nv) reaches 0.25 D.-   A “near-vision nasal half-width of refractive power” N_(P,nv) is    defined for the optical function of a near-vision unifocal lens, as    the angular distance, at constant lowering angle α, between the    proximate vision gaze direction (α_(PV), β_(PV)) and a gaze    direction (α^(PV), β_(NP)) on the nasal side of the lens where the    refractive power P_(αPV,βNP) reaches 0.25 D.-   A “near-vision temporal half-width of module of resulting    astigmatism” T_(A,nv) is defined for the optical function of a    near-vision unifocal lens, as the angular distance, at constant    lowering angle α, between the proximate vision gaze direction    (α_(PV), β_(PV)) and a gaze direction (α_(PV), β_(TA,nv)) on the    temporal side of the lens where the module of resulting astigmatism    Asr_(αPV,βNA,nv) reaches 0.25 D.-   A “near-vision nasal half-width of module of resulting astigmatism”    N_(A,nv) is defined for the optical function of a near-vision    unifocal lens, as the angular distance, at constant lowering angle    α, between the proximate vision gaze direction (α_(PV), β_(PV)) and    a gaze direction (α_(PV), β_(NA,nv)) on the nasal side of the lens    where the module of resulting astigmatism Asr_(αPV,βNA,nv) reaches    0.25 D.-   A “far-vision gaze direction” is defined for a lens, as the vision    gaze direction corresponding to the distant (far) reference point,    and thus α_(FV), where the refractive power is substantially equal    to the prescribed power in far vision. It may also be defined as the    gaze direction corresponding to the fitting cross, in which case    α=β=0°. Within the present disclosure, far-vision is also referred    to as distant-vision.-   A “far-vision temporal half-width of refractive power” T_(P,nv) is    defined for the optical function of a progressive lens, as the    angular distance, at constant lowering angle α, between the distant    (far) vision gaze direction (α_(FV), β_(FV)) and a gaze direction    (α_(FV), β_(TP,fv)) on the temporal side of the lens where the    refractive power P_(αFV,βTP,fv) reaches the value of the prescribed    far vision mean power P_(FV) for the lens plus one quarter of the    prescribed addition A for the lens:

P _(αFV,βTP,fv) =P _(FV)+(¼)*A

-   A “far-vision nasal half-width of refractive power” N_(P,fv) is    defined for the optical function of a progressive lens, as the    angular distance, at constant lowering angle α, between the    proximate vision gaze direction (α_(PV), β_(PV)) and a gaze    direction (α_(FV), β_(NP, fv)) on the nasal side of the lens where    the refractive power P_(αFV,βNP,fv) reaches the value of the    prescribed far vision mean power P_(FV) for the lens plus one    quarter of the prescribed addition A for the lens:

P _(αFV,βNP,fv) =P _(FV)+(¼)*A

-   A “far-vision temporal half-width of module of resulting    astigmatism” T_(A,fv) is defined for the optical function of a    progressive lens, as the angular distance, at constant lowering    angle α, between the far vision gaze direction (α_(FV), β_(FV)) and    a gaze direction (α_(FV), P_(TA,fv)) on the temporal side of the    lens where the module of resulting astigmatism Asr_(αFV,βTA,fv)    reaches the value of one quarter of the prescribed addition A for    the lens:

Asr _(αFV,βTA,fv) =A/4

-   A “far-vision nasal half-width of module of resulting astigmatism”    N_(A,fv) is defined for the optical function of a progressive lens,    as the angular distance, at constant lowering angle α, between the    far vision gaze direction (α_(FV), β_(FV)) and a gaze direction    (α_(FV), β_(NA,fv)) on the nasal side of the lens where the module    of resulting astigmatism Asr_(αFV,βNA,fv) reaches the value of one    quarter of the prescribed addition A for the lens:

Asr _(αFV,βNA,fv) =A/4

-   A “far-vision temporal half-width of refractive power” T_(P,fv) is    defined for the optical function of a far-vision unifocal lens, as    the angular distance, at constant lowering angle α, between the    distant (far) vision gaze direction (α_(FV), β_(FV)) and a gaze    direction (α_(FV), β_(TP,fv)) on the temporal side of the lens where    the refractive power P_(αFV,βTP,fv) reaches the value of 0.25 D.-   A “far-vision nasal half-width of refractive power” N_(P,fv) is    defined for the optical function of a far-vision unifocal lens, as    the angular distance, at constant lowering angle α, between the    proximate vision gaze direction (α_(FV), P_(FV)) and a gaze    direction (α_(FV), β_(NP,fv)) on the nasal side of the lens where    the refractive power P_(αFV,βNP,fv) reaches the value of 0.25 D.-   A “far-vision temporal half-width of module of resulting    astigmatism” T_(A,fv) is defined for the optical function of a    far-vision unifocal lens, as the angular distance, at constant    lowering angle α, between the far vision gaze direction (α_(FV),    β_(FV)) and a gaze direction (α_(FV), β_(TA,fv)) on the temporal    side of the lens where the module of resulting astigmatism    Asr_(αFV,βTA,fv) reaches the value of 0.25 D.-   A “far-vision nasal half-width of module of resulting astigmatism”    N_(A,fv) is defined for the optical function of a far-vision    unifocal lens, as the angular distance, at constant lowering angle    α, between the far vision gaze direction (α_(FV), β_(FV)) and a gaze    direction (α_(FV), β_(NA,fv)) on the nasal side of the lens where    the module of resulting astigmatism Asr_(αFV,βNA,fv) reaches the    value of 0.25 D.-   A “temporal half-width” and a “nasal half-width” may be defined by    analogy for other optical parameters, such as the parameters listed    below; and/or for other visions areas as listed below; and naturally    for a lens intended for a left eye LE and/or a lens for a right eye    RE;-   “Useful zones of the lens” designate areas of the lens which are    intended to be used by the wearer under certain circumstances. This    includes useful areas in the parts of the lens for near-vision,    distant-vision, and intermediate-vision; areas such as those for    central vision, and peripheral vision; and combinations of the    foregoing, e.g. central near vision, peripheral intermediate vision,    etc. Useful zones may vary from one wearer to the other. Further,    for a single wearer, useful zones may also vary when taking into    account the general context in which the lenses are to be worn, and    thus are activity dependent (lenses and hence eyeglasses for    practicing sport, applying makeup, shaving, reading, using an    e-tablet or a smartphone, writing at the desk, cooking, etc). The    useful zone may also refer to the entirety of the lens. Useful zones    may be determined by eye tracking, for example with tracking    glasses.-   “Optical parameters” are known in the art. According to the    invention, an optical parameter (π) is a criterion that has an    impact on visual performance.    -   Said optical parameter may be selected from:    -   any one of central vision optical criteria (CVOC) selected from        the group comprising: power in central vision, astigmatism in        central vision, high order aberration in central vision, acuity        in central vision, prismatic deviation in central vision, ocular        deviation, object visual field in central vision, image visual        field in central vision, magnification in central vision, or a        variation of preceding criteria;    -   any one of peripheral vision optical criteria (PVOC) selected        from the group comprising: power in peripheral vision,        astigmatism in peripheral vision, high order aberration in        peripheral vision, pupil field ray deviation, object visual        field in peripheral vision, image visual field in peripheral        vision, prismatic deviation in peripheral vision, magnification        in peripheral vision, or a variation of preceding criteria;    -   any one of global optical criteria (GOC) selected from the group        comprising: magnification of the eye, temple shift, or a        variation of preceding criteria;    -   any one of surface criteria (SC) selected from the group        comprising: front or back mean curvature, front or back minimum        curvature, front or back maximum curvature, front or back        cylinder axis, front or back cylinder, front or back mean        sphere, front or back maximum sphere, front or back minimum        sphere or a variation of preceding criteria,    -   the maximal value (respectively, minimal value, peak-to-valley        value, maximal gradient value, minimal gradient value, maximal        slope value, minimal slope value, average value) of any one of        the preceding criteria, in one or more useful zones of the lens        for near-vision, distant-vision, and intermediate-vision.    -   For example, said optical parameter may be the maximal value        (respectively, minimal value, peak-to-valley value, maximal        gradient value, minimal gradient value, maximal slope value,        minimal slope value, average value) of any one of resulting        astigmatism, refractive power gradient, mean sphere gradient of        the front surface, cylinder of the front surface.    -   for one given gaze direction,    -   over one zone of the lens, e.g. in one or more useful zones of        the lens for central vision, peripheral vision, near-vision,        distant-vision, and intermediate-vision, or combinations        thereof, or    -   where applicable, over the entire lens.-   “Central vision” (also referred as “foveal vision”) describes the    work of the fovea, a small area in the center of the retina that    contains a rich collection of cones. In a central vision situation,    an observer looks at an object which stays in a gaze direction and    the fovea of the observer is moved to follow the object. Central    vision permits a person to read, drive, and perform other activities    that require fine and sharp vision;-   “Peripheral vision” describes the ability to see objects and    movement outside of the direct line of vision. In a peripheral    vision situation, an observer looks in a fixed gaze direction and an    object is seen out of this direct line of vision. The direction of a    ray coming from the object to the eye is then different from the    gaze direction and is referred as peripheral ray direction.    Peripheral vision is mainly the work of the rods, photoreceptor    cells located outside the fovea of the retina;-   A “peripheral ray direction” is defined by two angles measured with    regard to reference axes centered on the eye entrance pupil and    moving along the gaze direction axis;-   “Power criterion in central vision” refers to refractive power    generated by the lens when the wearer observes an object in central    vision;-   “Astigmatism” refers to astigmatism generated by the lens, or to    residual astigmatism (resulting astigmatism) which corresponds to    the difference between the prescribed astigmatism (wearer    astigmatism) and the lens-generated astigmatism; in each case, with    regards to amplitude or both amplitude and axis;-   “Astigmatism criterion in central vision” refers to astigmatism    criteria in central vision, selected from astigmatism generated by    the lens, or to residual astigmatism (resulting astigmatism) which    corresponds to the difference between the prescribed astigmatism    (wearer astigmatism) and the lens-generated astigmatism; in each    case, with regards to amplitude or both amplitude and axis;-   “Higher-order aberrations in central vision” describe aberrations    that modify the blurredness of the image of the object observed by    the wearer in central vision besides the commonly residual power and    residual astigmatism, for example, spherical aberration and coma.    The orders by which aberrations are referred to are generally orders    expressed by Zernike polynomial representation;-   “Peripheral power” is defined as the power generated by the lens    when the wearer observes an object in peripheral vision;-   “Peripheral astigmatism” is defined as the astigmatism generated by    the lens as regards amplitude, or both amplitude and the axis;-   “Ocular deviation” is defined in central vision and describes the    fact that adding a lens causes an eye to rotate in order to stay    focused on the same object compared without lens. The angle can be    measured in prismatic diopters or degree;-   “Object visual field in central vision” is defined in the object    space by the portion of space that the eye can observe scanning an    angular portion of the lens determined by at least two gaze    directions. For instance, these gaze directions can be defined by    the shape of the spectacle frame or by an aberration level that    hinders visualizing the object space with a good enough sharpness;-   “Image visual field in central vision in the image space” is defined    for a determined and fixed object visual field in central vision in    the object space (eye space), as the angular portion scanned by the    eye to visualize the visual field in the object space;-   “Higher-order aberrations in peripheral vision” describe aberrations    that modify the blurredness of the image of the object observed by    the wearer in peripheral vision besides the commonly residual    peripheral power and residual peripheral astigmatism, for example,    peripheral spherical aberration and peripheral coma. The orders by    which aberrations are referred to are generally orders expressed by    Zernike polynomial representation;-   “Pupil field ray deviation” describes that a ray coming from an    object located in the peripheral field of view is modified by adding    a lens on its path to the eye entrance pupil;-   “Object visual field in peripheral vision” is defined in the object    space. It is the portion of space that the eye can observe in the    peripheral visual field of view (while the eye is looking in a fixed    direction) defined by at least two rays issued from the center of    eye entrance pupil. For instance, these rays can be defined by the    shape of the spectacle frame or by an aberration level that hinders    visualizing the object space with a good enough sharpness;-   “Image visual field in peripheral vision” is defined for a    determined and fixed peripheral object visual field as the    corresponding angular portion in the image space viewed by the    peripheral vision of the eye;-   “Prismatic deviation in central vision” is defined in the object    space by the angular deviation of a ray issued from the center of    rotation of the eye introduced by the quantity of prism of the lens;-   “Prismatic deviation in peripheral vision” is the angular deviation    of a ray issued from the center of the entrance pupil introduced by    the quantity of prism of the lens;-   “Magnification in central/peripheral vision” is defined as the ratio    between the apparent angular size (or the solid angle) of an object    seen in central/peripheral vision without lens and the apparent    angular size (or the solid angle) of an object seen through the lens    in central/peripheral vision;-   “Magnification of the eye” is defined as the magnification of the    eye of the wearer assessed by an observer;-   “temple shift” is defined as the offset of the wearer temple    assessed by an observer;-   A “minimum curvature” CURV_(min) is defined at any point on an    aspherical surface by the formula:

${CURV}_{\min} = \frac{1}{R_{\max}}$

-   -   where R_(max) is the local maximum radius of curvature,        expressed in meters and CURV_(min) is expressed in m⁻¹.

-   A “maximum curvature” CURV_(max) can be defined at any point on an    aspheric surface by the formula:

${CURV}_{\max} = \frac{1}{R_{\min}}$

-   -   where R_(min) is the local minimum radius of curvature,        expressed in meters and CURV_(max) is expressed in m⁻¹.

-   “Minimum and maximum spheres” labeled SPH_(min) and SPH_(max) can be    deduced according to the kind of surface considered.    -   When the surface considered is the object side surface(front        surface), the expressions are the following:

${SPH}_{\min} = {{( {n - 1} )*{CURV}_{\min}} = \frac{n - 1}{R_{\max}}}$and${SPH}_{\max} = {{( {n - 1} )*{CURV}_{\max}} = \frac{n - 1}{R_{\min}}}$

-   -   where n is the refractive index of the constituent material of        the lens.    -   If the surface considered is an eyeball side surface (rear        surface), the expressions are the following:

${SPH}_{\min} = {{( {1 - n} )*{CURV}_{\min}} = \frac{1 - n}{R_{\max}}}$and${SPH}_{\max} = {{( {1 - n} )*{CURV}_{\max}} = \frac{1 - n}{R_{\min}}}$

-   -   where n is the refractive index of the constituent material of        the lens.

-   A “mean sphere” SPH_(mean) at any point on an aspherical surface can    also be defined by the formula:

${SPH}_{mean} = {\frac{1}{2}( {{SPH}_{\min} + {SPH}_{\max}} )}$

-   -   The expression of the mean sphere therefore depends on the        surface considered:        -   if the surface is the object side surface,

${SPH}_{mean} = {\frac{n - 1}{2}( {\frac{1}{R_{\min}} + \frac{1}{R_{\max}}} )}$

-   -   -   if the surface is an eyeball side surface,

${SPH}_{mean} = {\frac{1 - n}{2}( {\frac{1}{R_{\min}} + \frac{1}{R_{\max}}} )}$

-   -   -   A cylinder CYL is also defined by the formula            CYL=|SPH_(max)−SPH_(min)|.

-   A “cylinder axis” γ_(AX) is the angle of the orientation of the    maximum curvature CURV_(max) with relation to a reference axis and    in the chosen direction of rotation. In the TABO convention, the    reference axis is horizontal (the angle of this reference axis is    0°) and the direction of rotation is counterclockwise for each eye,    when looking to the wearer (0°≦γ_(AX)≦180°). An axis value for the    cylinder axis γ_(AX) of +45° therefore represents an axis oriented    obliquely, which when looking to the wearer, extends from the    quadrant located up on the right to the quadrant located down on the    left.    -   The characteristics of any aspherical face of the lens may be        expressed by means of the local mean spheres and cylinders.    -   A surface may thus be locally defined by a triplet constituted        by the maximum sphere SPH_(max), the minimum sphere SPH_(min)        and the cylinder axis γ_(AX). Alternatively, the triplet may be        constituted by the mean sphere SPH_(mean), the cylinder CYL and        the cylinder axis T_(AX).

-   “micro-markings” have been made mandatory on progressive lenses by    the harmonized standard ISO 8990-2. “Temporary markings” may also be    applied on at least one of the two surfaces of the lens, indicating    positions of control points (reference points) on the lens, such as    a control point for far-vision, a control point for near-vision, a    prism reference point and a fitting cross for instance. The prism    reference point PRP is considered here at the midpoint of the    straight segment which connects the micro-markings. If the temporary    markings are absent or have been erased, it is always possible for a    skilled person to position the control points on the lens by using a    mounting chart and the permanent micro-markings. Similarly, on a    semi-finished lens blank, standard ISO 10322-2 requires    micro-markings to be applied. The centre of the aspherical surface    of a semi-finished lens blank can therefore be determined as well as    a referential as described above.

-   “inset” is known in the art and may be defined as follows. In a    progressive addition lens, the near-vision point (the near-vision    point corresponds to the intersection with the gaze direction    allowing the wearer to gaze in near-vision, this gaze direction    belonging to the meridian line) can be shifted horizontally with    respect to a vertical line passing through the distance-vision    point, when the lens is in a position of use by its wearer. This    shift, which is in the direction of the nasal side of the lens, is    referred to as “inset”. It generally depends on a number of    parameters, such as the optical power of the lens, the distance of    observation of an object, the prismatic deviation of the lens and    the eye-lens distance, notably. The inset may be an entry parameter    selected by an optician at the time of lens order. Inset may be    determined by computation or by ray tracing based upon the order    data (prescription data).

-   “Ophthalmic lens material composition” refers to any composition    suitable for making an ophthalmic lens. The skilled person is    familiar with such compositions. Examples includes compositions of    organic glass, such as of thermoplastic or thermoset materials,    which may be selected from the group consisting of polycarbonates,    polyurethanes, poly(thiourethanne), polyamides, polyimides,    polysulfones, polycarbonate-ethylene terephthalate copolymers,    polyolefins such as polynorbornenes, allyl diglycol carbonate    homopolymers or copolymers, (meth)acrylic homopolymers and    copolymers, thio(meth)acrylic homopolymers and copolymers, epoxy    resins and episulfide resins.

-   “Wearer data” (WD) designates one or more data obtained on the    wearer. Wearer data generally comprise “wearer prescription data”    (WPD) and/or “wearer biometry data” (WBD). Prescription data are    defined above. Wearer biometry data include data pertaining to the    morphology of the wearer, and typically include one or more of    monocular pupillary distance, inter-pupillary distance, axial length    of the eye, position of the center of rotation of the eye (CRE).    Wearer data may also comprise “wearer frame data”, which are data    linked to the frame worn by the wearer such as pantoscopic angle,    wrap angle or vertex distance. Wearer data may also include behavior    data such as head/eye gain, or posture data such as CAPE angle. The    wearer data are generally provided for each eye, but may also    comprise binocular biometry data.

-   “Wearer handedness data” (WHD) refers to a data indicating the    wearer handedness. Such data may be qualitative (left-handed or    right-handed) or quantitative, for example in the form of a    handedness parameter (H) taking a value of between −100 and +100, as    described thereafter.

-   “Frame data” (FD) refers to a set of one or more data characterizing    an eyeglasses frame. Said data may comprise one or more of    dimensions of the lens to be fitted (length and height), inner rim    shape of the frame for intended fitting of the lenses, distance    between lenses (DBL), convexity of the frame, tilt angle of the    frame rims, etc. Frame data may also extend to further information    such as type of lens design, lens material, selection of one or more    possible coatings on the lenses, etc). Frame data may be obtained    through physical measurements on an actual frame, for example using    a frame reader. Frame data may also consist in a reference from a    catalogue or from a set (range) of predetermined frames.

-   “Lens data” (LD) refers to a set of one or more data characterizing    an ophthalmic lens. Said data comprise data defining one or more    geometrical (surface) characteristics and/or one or more optical    characteristics of the lens, such as the optical index of the lens    material. Such characteristics may be selected amongst the optical    parameters listed above. Lens data can be in the form of an    electronic file, for example a surface file. Said surface file may    correspond to the finished back surface of a lens to be    manufactured, for example wherein the lens is obtainable by    machining the back surface of a semi-finished blank. Said surface    file may alternatively correspond to the front surface of a lens to    be manufactured. Said lens data may also comprise two surface files,    one for each the front and the rear surface, their relative    positions and the refractive index of the lens material.

-   “Target optical function of an ophthalmic lens” represents the    global optical performance to be reached for said lens, i.e. the set    of characteristics the ophthalmic lens should have. In the context    of the present invention and in the remainder of the description,    the term “target optical function of the lens” is used for    convenience. This use is not strictly correct in so far as a target    optical function is defined with respect to a given wearer, for a    system of ophthalmic lens and ergorama.    -   The optical target function of such system is a set of target        values of one or more optical parameter(s) defined in a number        of given gaze directions. A target value is defined for each        optical parameter in each given gaze direction. The resulting        set of optical parameter target values is the target optical        function.    -   In one aspect, a target optical function may be defined with a        single optical parameter, for example power or residual        astigmatism or astigmatism. In another aspect, a target optical        function may be defined with two optical parameters, such as        optical power and residual astigmatism, or optical power and        astigmatism. In another aspect, a target optical function may be        defined with further optical parameters, such as a linear        combination of optical power and astigmatism, or other        parameters involving aberrations of higher order may be        considered. The number N of optical parameters used in the        target optical function depends on the desired level of        precision. Indeed, the more optical parameters, the more likely        the resulting lens is to satisfy the wearer's needs. However,        increasing the number N of parameters may result in increasing        the time taken for calculation. The choice of the number N of        parameters considered will may be a trade-off between these two        requirements. More details about target optical functions,        optical parameter definition and optical parameter evaluation        can be found in WO2011/042504.    -   A target optical function is used in a lens “optical        optimization” process. Said process generally comprises        -   a step of defining a target optical function, wherein a            target optical function is defined. Said target optical            function is generally designed by taking into account wearer            prescription data, wearer biometry data, and other factors            such as wearer behavior, including head/eye behavior;        -   a step of defining an initial lens;        -   a step of defining a current lens, with a current optical            function being defined for said current lens, the current            lens being initially defined as the initial lens;        -   one or more steps of optical optimization for minimizing the            difference between the current optical function and the            target optical function, for example by modification of the            current lens.    -   From the above, the skilled person understands that “current        optical function” or an “intermediate optical function” is        defined for a given lens. Said current or intermediate optical        function of a current or intermediate lens is the set of values        reached by said lens for the same optical parameter(s) in the        same gaze directions as in the target optical function. The aim        of the optical optimization is to minimize the differences        between the current optical function and the target optical        function. The optimization may be performed by iteration, for        example by using a ray-tracing method. An example of lens        optical optimization using target definition is described in        EP-A-0 990 939.

DETAILED DESCRIPTION OF THE DRAWINGS Providing Ophthalmic Lenses

The present invention relates to a system and to methods for providingophthalmic lenses, intended to be worn by a wearer, wherein the lens isdesigned as a function of the wearer's handedness. The fact that thelens is designed as a function of the wearer's handedness indicates thatat least one of the lens properties are selected taking into account thewearer's handedness. Such properties include lens surface parameters andlens optical parameters.

The lens is preferably a spectacle multifocal progressive ophthalmiclens, more preferably a multifocal progressive ophthalmic lens, but notlimited thereto.

Lens Supply System

The present invention provides an ophthalmic lens supply system forproviding an ophthalmic lens intended to be worn by a wearer.

The ophthalmic lens supply system comprises first processing means (PM1)suitable for placing an order of an ophthalmic lens. Said firstprocessing means (PM1) are located at a lens ordering side (LOS). Thelens ordering side (LOS) is typically at the premises of an eye careprofessional or optician where lenses are ordered for wearers(customers).

The first processing means (PM1) comprise:

-   -   inputting means (IM1) suitable for the input of wearer data        (WD); wearer data (WD) include wearer prescription data (WPD)        and possibly wearer biometry data (WBD): said first processing        means are in particular suitable for the input of wearer        prescription data (WPD),    -   inputting means (IM2) suitable for the input of wearer        handedness data (WHD).

The ophthalmic lens supply system further comprises second processingmeans (PM2) suitable for providing lens data (LD) based upon wearer data(WD, WPD, WBD), and wearer handedness data (WHD). Said second processingmeans (PM2) are located at a lens determination side (LDS) and maycomprise outputting means (OM) suitable for outputting said lens data(LD). According to the invention, said lens data may be transmitted fromthe lens designing side (LDS) to a lens manufacturing side (LMS) bysecond transmitting means (TM2).

The lens determination side (LDS) is equipped with processing means thatmay advantageously be suitable for performing any one of the lensdetermination methods as described therein or may advantageouslycomprise a computer program product as described thereafter.

The ophthalmic lens supply system further comprises first transmissionmeans (TM1) suitable for transmitting said wearer data (WD, WPD, WBD)and wearer handedness data (WHD), from said first processing means (PM1)to said second processing means (PM2).

Each of the above imputing means (IM) may be any inputting meanssuitable for the input of the relevant data. Said inputting means arepreferably selected for facilitated interface (e.g. may be used inconnection with displaying means), and may be a keyboard from a computersuch as a PC or laptop, tablet, handset, terminal, remote, etc.

The system of the invention may further comprise inputting means (IM3)suitable for the input of frame data (FD) wherein said frame is theframe intended for fitting the lens, and/or inputting means (IM4)suitable for the input of wearer biometry data (WBD).

According to the invention, the inputting means (IM1-IM4) may bedistinct of each other or (partially or fully) combined. For example,one may have (IM1)=(IM2) or (IM1)=(IM2)=(IM4), etc.

In one aspect, the ophthalmic lens supply system of the inventionfurther comprises

-   -   manufacturing means (MM) suitable for manufacturing an        ophthalmic lens based upon lens data (LD), wherein said        manufacturing means are located at a lens manufacturing side        (LMD), and    -   second transmission means (TM2) suitable for transmitting said        lens data (LD) from said second processing means (PM2) to said        manufacturing means (MM).

The lens manufacturing side is generally located in an optical lab,namely a place equipped with manufacturing means for manufacturinglenses following lens orders, based upon lens data previously obtainedor generated.

Lens manufacturing means (MM) are known in the art, and the skilledperson is familiar with suitable manufacturing means. Said manufacturingmeans may include one or more of surfacing including digital surfacing,polishing, edging means, etc. The lens manufacturing side (LMS) maycomprise a combination of manufacturing means, including severaldifferent surfacing means, and/or several polishing means, etc. The lensmanufacturing side may further comprise inputting means suitable forreceiving the information from said second processing means and furthertransmit the information to the relevant manufacturing means.

The lens manufacturing side (LMS) may further comprise third processingmeans (PM3). Third processing means may send further data, for examplerelative to manufacturing means, such as the designation (selection) ofspecific manufacturing means or manufacturing rules to be used withspecific manufacturing means, for example the selection of a givenmanufacturing protocol or the identification of specific manufacturingparameters regarding the settings of specific manufacturing means.

In the system of the invention, the transmitting means (TM1, TM2) maycomprise all types of suitable transmission means. The person skilled inthe art is familiar with suitable transmitting means useful in the fieldof lens supply systems. Suitable means include electroniccommunications, such as by internet connections, for example via one ormore servers, e-mail communication, and the like.

In one aspect of the invention, the first and/or the second and/or thethird processing means (PM1, PM2, PM3) may be a computer entity and maycomprise a memory (MEM). The computer entities may be connected to eachother through one or more servers. Said servers may comprise storingmeans in the form of a memory.

Memories are known in the art and the skilled person is familiar withmemories that that suitable for implementation within a lens supplysystem. The memory may be suitable for storing data, such as: inputdata, output data, intermediate data (such as intermediate computationresults). The memory may be useful as a working memory and/or to storesequence of instructions. The memory may be provided in one or morestoring elements/means, and may be part of a server.

An exemplary ophthalmic lens supply system of the invention isrepresented schematically at FIG. 23.

Methods for Ophthalmic Lens Determination

The present invention provides a computer-implemented method for thedetermination of an ophthalmic lens intended to be worn by a wearer.

In one aspect, said method comprising the following steps:

-   -   a step (SH) of providing data on the wearer's handedness,    -   a step (SL) of determining the ophthalmic lens, wherein the step        (SL) for determining the ophthalmic lens takes into account the        wearer's handedness.

In the step (SH), the data on wearer's handedness may result from(possibly instant) determination at the optician's, but may also havebeen previously obtained, by the optician or by a third-party. Forexample, the data on wearer's handedness may have been previouslydetermined, and thus may have been already registered in the personalfile (customer file) of the wearer and thus may be readily copied orimported from the wearer's file, along with other information such asdate of birth, address, etc. Methods for determining a wearer'shandedness are described in detail thereafter.

In one aspect, the method of the invention comprises a step (SH) and astep (SL) as defined above, wherein said step (SL) of determining theophthalmic lens is selected from:

-   -   a step (SSR) for selecting a lens from a range of ophthalmic        lenses designed according to wearer handedness, or    -   a calculation step (CS), or    -   a determination step (OPTIM) by optical optimization.

Exemplary methods of the invention are represented schematically at FIG.24.

Methods for Ophthalmic Lens Determination by Selection

In one aspect, the present invention provides a computer-implementedmethod for the determination of an ophthalmic lens, wherein said methodscomprises a step (SH) as defined above, and wherein said step (SL) is astep (SSR) for selecting a lens from a range of ophthalmic lensesdesigned according to wearer handedness.

According to this method, the eye care specialist may select, forexample from a catalogue, for example online catalogue, suitable lensesas a function of the wearer handedness.

Methods for Ophthalmic Lens Determination by Calculation

In one aspect, the present invention provides a computer-implementedmethod for the determination of an ophthalmic lens intended to be wornby a wearer, wherein said method comprising the following steps:

a step (SH) of providing data on the wearer's handedness, and

-   -   a step (SL) of determining the ophthalmic lens, wherein the step        (SL) for determining the ophthalmic lens is a calculation step        (CS) and takes into account the wearer's handedness.

In one embodiment, the calculation step (CS) may be one described and/orclaimed in U.S. Pat. No. 6,786,600. According to an embodiment, thecalculation step comprises a step of providing a set of surfaces, eachsuitable for a given prescription range, and a step of combining onesurface from said set with a spherical or toric surface. According to anembodiment, two surfaces or more are selected and weighted, before beingcombined, so as to reach the desired optical performance as a functionof handedness (for example, by introducing asymmetry in thenasal/temporal half-widths as a function of handedness, see below).

In another embodiment, the calculation step (CS) may comprise thefollowing steps:

-   -   a step (S1) of providing a set of surfaces,    -   a step (S2) of selecting at least two surfaces from said set of        surfaces,    -   a step (S3) of summing or subtracting the selected surfaces so        as to obtained a selected lens;        wherein said set of surfaces comprises handedness-dependent        surfaces and the step of selecting at least two surfaces        comprises selecting at least one handedness-specific surface as        a function of the wearer's handedness.        Methods for Ophthalmic Lens Determination by Optical        Optimization with Respect to a Determined Target Optical        Function

The general principle of optical optimization is described in thedefinition section above. The present invention provides acomputer-implemented method for the determination of an ophthalmic lensintended to be worn by a wearer, wherein said wearer was issued aprescription containing prescription data and wherein the ophthalmiclens is preferably a progressive ophthalmic lens.

The present invention provides a computer-implemented method for thedetermination of an ophthalmic lens comprising a step (SH) as definedabove and a step of determining the lens (SL), wherein said step (SL) isa determination step (OPTIM) by optical optimization.

The determination step by optical optimization (OPTIM) may comprise thefollowing steps:

-   -   a step (Sa) of selecting an ergorama,    -   a step (Sb) of defining a target optical function for said lens        (in fact, lens/ergorama system) as a function of the wearer's        prescription data,    -   a step (Sc) of carrying out optimization with respect to said        defined target optical function.

In one aspect, the step (Sc) may be a step of carrying out optimizationby:

-   -   selecting an initial lens,    -   defining a current lens, a current optical function being        defined for the current lens, the current lens being initially        defined as the initial lens,    -   carrying out an optical optimization for minimizing the        difference between the current optical function and the target        optical function, for example with a cost or a merit function.    -   The optical optimization is generally performed by modifying the        current lens. The current optical function may be obtained using        the ray-tracing method. The optical optimization may proceed by        iteration.

The above optical optimization (OPTIM) may be carried out in asequential way (for one eye, then for the other), or in parallel(simultaneously for both eyes).

Methods for Ophthalmic Lens Determination by Optical Optimization withRespect to a Determined Target Optical Function, Using aHandedness-Dependent Ergorama

In one embodiment, said ergorama is handedness-dependent. An ergoramamay be defined as a function of handedness by asymmetrizing the ergoramain the Cyclopean system of coordinates. For example it is possible toasymmetrize object distance (or proximity) as a function of handedness.In one example, proximity (distance⁻¹) may be enhanced in a near visionzone on the hand-writing side.

In another embodiment, said ergorama is handedness-dependent andactivity-dependent. Accordingly, the ergorama is designed as a functionof the wearer's handedness and of the intended activity when wearing thelens (doing sports, reading, going to the movies, working at desk,etc.).

In another embodiment, the optical optimisation (OPTIM) is such thatsaid ergorama is handedness-dependent and optionally activity-dependent,and/or such that the target optical function is designed as a functionof the wearer's handedness (see below).

Target Optical Functions with Asymmetry in Nasal/Temporal Half-Widths asa Function of Handedness

In the method of the invention, the determination step by opticaloptimization (OPTIM) may comprise a step (Sb) of defining a targetoptical function, wherein step (Sb) comprises a step of asymmetrizingthe nasal/temporal field half-widths of one or more of the following:

-   -   the near-vision zone with respect to a proximate-vision gaze        direction,    -   the intermediate-vision zone with respect to the meridian line,    -   the distant-vision zone with respect to a distant-vision gaze        direction, of the target optical function as a function of the        wearer's handedness.

In one aspect, handedness is taken into account in that nasal/temporalhalf-widths of the target optical function are made asymmetric as afunction of the wearer's handedness.

In one aspect, the target optical function is asymmetric in that thenasal/temporal half-widths of one or more of the following:

-   -   the near-vision zone with respect to a proximate-vision gaze        direction,    -   the intermediate-vision zone with respect to the meridian line,    -   the distant-vision zone with respect to a distant-vision gaze        direction, are asymmetric as a function of the wearer's        handedness.

According to one aspect, the target optical function is such that thenear-vision nasal/temporal half-widths are asymmetric as a function ofthe wearer's handedness.

The half-widths may be defined for any optical parameter as describedherein, in particular for the module of resulting astigmatism and/or forrefractive power.

In one embodiment, for a left-handed wearer, the ratio of the differenceover the sum of near-vision temporal and nasal half-widths of refractivepower is set to a value less than or equal substantially to 0((T_(P,nv)−N_(P,nv))/(T_(P,nv)+N_(P,nv))≦0) and/or the ratio of thedifference over the sum of near-vision temporal and nasal half-widths ofmodule of resulting astigmatism is set to a value less than or equalsubstantially to 0 ((T_(A,nv)−N_(A, nv))/(T_(A,nv)+N_(A,nv))≦0); theseratios may each individually or both be set to a value strictly inferiorthan 0, for example <−0.10, <−0.15, <−0.20, <−0.25. The lens ispreferably intended for the right eye of the wearer.

In another embodiment, for a left-handed wearer, the ratio of thedifference over the sum of near-vision temporal and nasal half-widths ofrefractive power is set to a value greater than or equal substantiallyto 0 ((T_(P,nv)−N_(P,nv))/(T_(P,nv)+N_(P,nv))≧0) and/or the ratio of thedifference over the sum of near-vision temporal and nasal half-widths ofmodule of resulting astigmatism is set to a value greater than or equalsubstantially to 0 ((T_(A,nv)−N_(A,nv))/(T_(A,nv)+N_(A,nv))≧0); theseratios may each individually or both be set to a value strictly greaterthan 0, for example >0.10, >0.15, >0.20, >0.25. The lens is preferablyfor the left-eye of the wearer.

In another embodiment, for a left-handed wearer, the ratio of thedifference over the sum of near-vision temporal and nasal half-widths ofrefractive power is set substantially to 0 ((T_(P,nv)−N_(P) _(—)_(nv))/(T_(P,nv)+N_(P,nv))=0) and/or the ratio of the difference overthe sum of near-vision temporal and nasal half-widths of module ofresulting astigmatism is set substantially to 0((T_(A,nv)−N_(A,nv))/(T_(A,nv)+N_(A,nv))=0).

The above target optical functions may be paired (RE/LE).

In one embodiment, for a right-handed wearer, the ratio of thedifference over the sum of near-vision temporal and nasal half-widths ofrefractive power is set to a value greater than or equal substantiallyto 0 ((T_(P,nv)−N_(P,nv))/(T_(P,nv)+N_(P,nv))≧0) and/or the ratio of thedifference over the sum of near-vision temporal and nasal half-widths ofmodule of resulting astigmatism is set to a value greater than or equalsubstantially to 0 ((T_(A,nv)−N_(A,nv))/(T_(A,nv)+N_(A,nv))≧0); theseratios may each individually or both be set to a value strictly greaterthan 0, for example >0.10, >0.15, >0.20, >0.25. The lens is preferablyintended for the right eye of the wearer.

In another embodiment, for a right-handed wearer, the ratio of thedifference over the sum of near-vision temporal and nasal half-widths ofrefractive power is set to a value less than or equal substantially to 0((T_(P,nv)−N_(P,nv))/(T_(P,nv)+N_(P,nv))≦0) and/or the ratio of thedifference over the sum of near-vision temporal and nasal half-widths ofmodule of resulting astigmatism is set to a value less than or equalsubstantially to 0 ((T_(A,nv)−N_(A,nv))/(T_(A,nv)+N_(A,nv))≦0); theseratios may each individually or both be set to a value strictly inferiorto 0, for example <−0.10, <−0.15, <−0.20, <−0.25. The lens is preferablyfor the left-eye of the wearer.

The above target optical functions may be paired (RE/LE).

According to one aspect, the target optical function is such that thefar-vision nasal/temporal half-width are asymmetric as a function of thewearer's handedness. Advantageously, the fields are more open(half-widths larger) on the side of the writing hand.

In one embodiment, for a left-handed wearer, the ratio of the differenceover the sum of far-vision temporal and nasal half-widths of refractivepower is set to a value less than or equal substantially to 0((T_(P,fv)−N_(P,fv))/(T_(P,fv)+N_(P,fv))≦0) and/or the ratio of thedifference over the sum of far-vision temporal and nasal half-widths ofmodule of resulting astigmatism is set to a value less than or equalsubstantially to 0 ((T_(A,fv)−N_(A, fv))/(T_(A,fv)+N_(A,fv))≦0); theseratios may each individually or both be set to a value strictly inferiorthan 0, for example <−0.10, <−0.15, <−0.20, <−0.25. The lens ispreferably intended for the right eye of the wearer.

In another embodiment, for a left-handed wearer, the ratio of thedifference over the sum of far-vision temporal and nasal half-widths ofrefractive power is set to a value greater than or equal substantiallyto 0 ((T_(P,fv)−N_(P,fv))/(T_(P,fv)+N_(P,fv)≧)0) and/or the ratio of thedifference over the sum of far-vision temporal and nasal half-widths ofmodule of resulting astigmatism is set to a value greater than or equalsubstantially to 0 (T_(A,fv)−N_(A,fv))/(T_(A,fv)+N_(A,fv))≧0; theseratios may individually each or both be set to a value strictly greaterthan 0, for example >0.10, >0.15, >0.20, >0.25. The lens is preferablyfor the left-eye of the wearer.

The above target optical functions may be paired (RE/LE).

In one embodiment, for a right-handed wearer, the ratio of thedifference over the sum of far-vision temporal and nasal half-widths ofrefractive power is set to a value greater than or equal substantiallyto 0 ((T_(P,fv)−N_(P,fv))/(T_(P,fv)+N_(P,fv))≧0) and/or the ratio of thedifference over the sum of far-vision temporal and nasal half-widths ofmodule of resulting astigmatism is set to a value greater than or equalsubstantially to 0 ((T_(A,fv)−N_(A,fv))/(T_(A,fv)+N_(A,fv))≧0); theseratios may each individually or both be set to a value strictly greaterthan 0, for example >0.10, >0.15, >0.20, >0.25. The lens is preferablyintended for the right eye of the wearer.

In another embodiment, for a right-handed wearer, the ratio of thedifference over the sum of far-vision temporal and nasal half-widths ofrefractive power is set to a value less than or equal substantially to 0((T_(P,fv)−N_(P,fv))/(T_(P,fv)+N_(P,fv))≦0) and/or the ratio of thedifference over the sum of far-vision temporal and nasal half-widths ofmodule of resulting astigmatism is set to a value less than or equalsubstantially to 0 ((T_(A,fv)−N_(A, fv))/(T_(A,fv)+N_(A,fv))≦0); theseratios may each individually or both be set to a value strictly inferiorto 0, for example <−0.10, <−0.15, <−0.20, <−0.25. The lens is preferablyfor the left-eye of the wearer.

The above target optical functions may be paired (RE/LE).

The above described asymmetries may be generalized to other opticalparameters π, whether in the near-vision zone (NV), in theintermediate-vision zone (IV) or in the far-vision zone (FV).

According to one aspect, the target optical function is such that thenasal/temporal half-widths are asymmetric as a function of the wearer'shandedness. The asymmetry may apply to resulting astigmatism and/orpower, whether in the far vision zone or in the near vision zone, andall combinations thereof. The handedness is advantageously taken intoaccount by means of a handedness value H. H depends solely on thewearer's handedness and may be determined as explained thereafter. Inparticular, H may be determined as illustrated in example 4.

On one embodiment,

-   -   for the right eye: (T_(P,nv)−N_(P) _(—)        _(nv))/(T_(P,nv)+N_(P,nv))=0.002*H, and/or    -   for the left eye:        (T_(P,nv)−N_(P,nv))/(T_(P,nv)+N_(P,nv))=−0.002*H.

In another embodiment,

-   -   for the right eye:        (T_(A,nv)−N_(A,nv))/(T_(A,nv)+N_(A,nv))=0.002*H, and/or    -   for the left eye:        (T_(A,nv)−N_(A,nv))/(T_(A,nv)+N_(A,fv))=−0.002*H.

In another embodiment,

-   -   for the right eye:        (T_(P,fv)−N_(P,fv))/(T_(P,fv)+N_(P,fv))=0.002*H, and/or    -   for the left eye:        (T_(P,fv)−N_(P,fv))/(T_(P,fv)+N_(P,fv))=−0.002*H.

In another embodiment,

-   -   for the right eye:        (T_(A,fv)−N_(A,fv))/(T_(A,fv)+N_(A,fv))=0.002*H, and/or    -   for the left eye:        (T_(A,fv)−N_(A,fv))/(T_(A,fv)+N_(A,fv))=−0.002*H.

The above lenses may be paired so as to form a pair of lenses (RE/LE).

As stated, the features may also be combined, for example:

In one embodiment, for the right eye:

-   -   (T_(P,nv)−N_(P) _(—) _(nv))/(T_(P,nv)+N_(P,nv))=0.002*H and    -   (T_(A,nv)−N_(A,nv))/(T_(A,nv)+N_(A,nv))=0.002*H.

In another embodiment, for the left eye:

-   -   (T_(P,nv)−N_(P,nv))/(T_(P,nv)+N_(P,nv))=−0.002*H and    -   (T_(A,nv)−N_(A,nv))/(T_(A,nv)+N_(A,nv))=−0.002*H.

In all the above embodiments, H may be determined as describedthereafter, notably as in example 4, and thus H may have a value between−100 and +100.

Further, for one target optical function, any one of the aboveembodiments regarding half-widths in near vision may be combined withany one of the above embodiments regarding half-widths in far vision.

Pair of Target Optical Functions with Asymmetry in Nasal/TemporalHalf-Widths as a Function of Handedness

According to one aspect, the invention provides a pair of target opticalfunctions of lenses intended for a wearer, wherein the nasal/temporalhalf-widths of the near-vision zone with respect to a proximate-visiongaze direction are asymmetric as a function of the wearer's handedness.

In one embodiment, for a left-handed wearer, the ratio of the differenceover the sum of near-vision temporal and nasal half-widths of refractivepower is set substantially to 0 for each lens of the pair ((T_(P) _(—)_(LE,nv)−N_(P) _(—) _(LE,nv))/(T_(P) _(—) _(LE,nv)+N_(P) _(—)_(LE,nv))=(T_(P) _(—) _(RE,nv)−N_(P) _(—) _(RE, nv))/(T_(P) _(—)_(RE,nv)+N_(P) _(—) _(RE,nv))=0) and/or the ratio of the difference overthe sum of near-vision temporal and nasal half-widths of module ofresulting astigmatism is set substantially to 0 for each lens of thepair ((T_(A) _(—) _(LE,nv)−N_(A) _(—) _(LE,nv))/(T_(A) _(—)_(LE,nv)+N_(A) _(—) _(LE,nv))=(T_(A) _(—) _(RE,nv)−N_(A) _(—)_(RE,nv))/(T_(A) _(—) _(RE,nv)+N_(A) _(—) _(RE,nv))=0).

In another embodiment, for a left-handed wearer, the ratio of thedifference over the sum of near-vision temporal and nasal half-widths ofrefractive power is set to a value less than or equal substantially to 0for the right-eye lens ((T_(P) _(—) _(RE,nv)−N_(P) _(—) _(RE,nv))/(T_(P)_(—) _(RE,nv)+N_(P) _(—) _(RE,nv))≦0) and/or the ratio of the differenceover the sum of near-vision temporal and nasal half-widths of module ofresulting astigmatism is set to a value less than or equal substantiallyto 0 for the right-eye lens ((T_(A) _(—) _(RE,nv)−N_(A) _(—)_(RE,nv))/(T_(A) _(—) _(RE,nv)+N_(A) _(—) _(RE,nv))≦0), and the ratio ofthe difference over the sum of near-vision temporal and nasalhalf-widths of refractive power is set to a value greater than or equalsubstantially to 0 for the left-eye lens ((T_(P) _(—) _(LE,nv)−N_(P)_(—) _(LE,nv))/(T_(P) _(—) _(LE,nv)−N_(P) _(—) _(LE,nv))≧0) and/or theratio of the difference over the sum of near-vision temporal and nasalhalf-widths of module of resulting astigmatism is set to a value greaterthan or equal substantially to 0 for the left-eye lens ((T_(A) _(—)_(LE,nv)−N_(A) _(—) _(LE,nv))/(T_(A) _(—) _(LE,nv)+N_(A) _(—)_(LE,nv))≧0).

In another embodiment, for a left-handed wearer, [(T_(P) _(—)_(LE,nv)−N_(P) _(—) _(LE,nv))/(T_(P) _(—) _(LE,nv)+N_(P) _(—)_(LE, nv))≧0 and (T_(P) _(—) _(RE,nv)−N_(P) _(—) _(RE,nv))/(T_(P) _(—)_(RE,nv)+N_(P) _(—) _(RE,nv))≦0] and/or [(T_(A) _(—) _(LE,nv)−N_(A) _(—)_(LE, nv))/(T_(A) _(—) _(LE,nv)+N_(A) _(—) _(LE,nv))≧0 and (T_(A) _(—)_(RE,nv)−N_(A) _(—) _(RE,nv))/(T_(A) _(—) _(RE,nv)+N_(A) _(—)_(RE,nv))≦0].

In one embodiment, for a left-handed wearer, [(T_(P) _(—) _(LE,nv)−N_(P)_(—) _(LE,nv))/(T_(P) _(—) _(LE,nv)+N_(P) _(—) _(LE,nv))>0 and (T_(P)_(—) _(RE,nv)−N_(P) _(—) _(RE,nv))/(T_(P) _(—) _(RE,nv)+N_(P) _(—)_(RE,nv))>0 and [(T_(A) _(—) _(LE,nv)−N_(A) _(—) _(LE, nv))/(T_(A) _(—)_(LE,nv)+N_(A) _(—) _(LE,nv))>0] and [(T_(A) _(—) _(RE,nv)−N_(A) _(—)_(RE,nv))/(T_(A) _(—) _(RE,nv)−N_(A) _(—) _(RE,nv))<0].

In one embodiment, for a left-handed wearer, [(T_(P) _(—) _(LE,nv)−N_(P)_(—) _(LE,nv))/(T_(P) _(—) _(LE,nv)+N_(P) _(—) _(LE,nv))>0.15,preferably >0.20, preferably >0.25, preferably >0.30 and (T_(P) _(—)_(RE,nv)−N_(P) _(—) _(RE, nv))/(T_(P) _(—) _(RE,nv)+N_(P) _(—)_(RE,nv))<−0.15, preferably <−0.20, preferably <−0.25, preferably <0.30]and/or [(T_(A) _(—) _(LE,nv)−N_(A) _(—) _(LE,nv))/(T_(A) _(—)_(LE,nv)+N_(A) _(—) _(LE,nv))>0.15, preferably >0.20, preferably >0.25,preferably >0.30 and (T_(A) _(—) _(RE,nv)−N_(A) _(—) _(RE,nv))/(T_(A)_(—) _(RE,nv)+N_(A) _(—) _(RE,nv))<−0.15, preferably <−0.20, preferably<−0.25, preferably <−0.30].

In another embodiment, for a right-handed wearer, the ratio of thedifference over the sum of near-vision temporal and nasal half-width ofrefractive power is set to a value greater than or equal substantiallyto 0 for the right-eye lens ((T_(P) _(—) _(RE,nv)−N_(P) _(—)_(RE,nv))/(T_(P) _(—) _(RE, nv)+N_(P) _(—) _(RE,nv))≧0) and/or the ratioof the difference over the sum of near-vision temporal and nasalhalf-width of module of resulting astigmatism is set to a value greaterthan or equal substantially to 0 for the right-eye lens ((T_(A) _(—)_(RE,nv)−N_(A) _(—) _(RE,nv))/(T_(A) _(—) _(RE,nv)+N_(A) _(—)_(RE,nv))≧0), and the ratio of the difference over the sum ofnear-vision temporal and nasal half-width of refractive power is set toa value less than or equal substantially to 0 for the left-eye lens((T_(P) _(—) _(LE,nv)−N_(P) _(—) _(LE,nv))/(T_(P) _(—) _(LE,nv)+N_(P)_(—) _(LE,nv))≦0) and/or the ratio of the difference over the sum ofnear-vision temporal and nasal half-width of module of resultingastigmatism is set to a value less than or equal substantially to 0 forthe left-eye lens ((T_(A) _(—) _(LE,nv)−N_(A) _(—) _(LE,nv))/(T_(A) _(—)_(LE,nv)+N_(A) _(—) _(LE,nv))≦0).

In another embodiment, for a right-handed wearer, the ratio of thedifference over the sum of near-vision temporal and nasal half-width ofrefractive power in the near vision zone is set to a value strictlygreater than 0 for the right-eye lens ((T_(P) _(—) _(RE,nv)−N_(P) _(—)_(RE, nv))/(T_(P) _(—) _(RE,nv)+N_(P) _(—) _(RE,nv))>0) and/or the ratioof the difference over the sum of near-vision temporal and nasalhalf-width of module of resulting astigmatism is set to a value strictlygreater than 0 for the right-eye lens ((T_(A) _(—) _(RE,nv)−N_(A) _(—)_(RE,nv))/(T_(A) _(—) _(RE,nv)+N_(A) _(—) _(RE,nv))>0), and the ratio ofthe difference over the sum of near-vision temporal and nasal half-widthof refractive power is set to a value strictly less than 0 for theleft-eye lens ((T_(P) _(—) _(LE, nv)−N_(P) _(—) _(LE,nv))/(T_(P) _(—)_(LE,nv)+N_(P) _(—) _(LE,nv))<0) and/or the ratio of the difference overthe sum of near-vision temporal and nasal half-width of module ofresulting astigmatism is set to a value strictly less than 0 for theleft-eye lens ((T_(A) _(—) _(LE,nv)−N_(A) _(—) _(LE,nv))/(T_(A) _(—)_(LE,nv)+N_(A) _(—) _(LE,nv))<0).

In another embodiment, for a right-handed wearer, [(T_(P) _(—)_(LE,nv)−N_(P) _(—) _(LE,nv))/(T_(P) _(—) _(LE,nv)+N_(P) _(—)_(LE,nv))≦0 and (T_(P) _(—) _(RE,nv)−N_(P) _(—) _(RE,nv))/(T_(P) _(—)_(RE,nv)+N_(P) _(—) _(RE,nv))≧0] and/or [(T_(A) _(—) _(LE,nv)−N_(A) _(—)_(LE,nv))/(T_(A) _(—) _(LE,nv)+N_(A) _(—) _(LE,nv))≦0 and (T_(A) _(—)_(RE,nv)−N_(A) _(—) _(RE,nv))/(T_(A) _(—) _(RE,nv)+N_(A) _(—)_(RE,nv))≧0].

In another embodiment, for a right-handed wearer, [(T_(P) _(—)_(LE,nv)−N_(P) _(—) _(LE,nv))/(T_(P) _(—) _(LE,fv)+N_(P) _(—)_(LE,nv))≦0 and (T_(P) _(—) _(RE,nv)−N_(P) _(—) _(RE,nv))/(T_(P) _(—)_(RE,nv)+N_(P) _(—) _(RE,nv))≧0] and/or [(T_(A) _(—) _(LE,nv)−N_(A) _(—)_(LE,nv))/(T_(A) _(—) _(LE,nv)+N_(A) _(—) _(LE,nv))≦0 and (T_(A) _(—)_(RE,nv)−N_(A) _(—) _(RE,nv))/(T_(A) _(—) _(RE,nv)+N_(A) _(—)_(RE,nv))>0].

In another embodiment, for a right-handed wearer, [(T_(P) _(—)_(LE,nv)−N_(P) _(—) _(LE,nv))/(T_(P) _(—) _(LE,nv)+N_(P) _(—)_(LE,nv))<−0.15, preferably <−0.20, preferably <−0.25, preferably <−0.30and (T_(P) _(—) _(RE,nv)−N_(P) _(—) _(RE,nv))/(T_(P) _(—) _(RE,nv)+N_(P)_(—) _(RE,fv))>0.15, preferably >0.20, preferably >0.25,preferably >0.30] and/or [(T_(A) _(—) _(LE,nv)−N_(A) _(—)_(LE,nv))/(T_(A) _(—) _(LE,nv)+N_(A) _(—) _(LE,nv))<−0.15, preferably<−0.20, preferably <−0.25, preferably <−0.30 and (T_(A) _(—)_(RE,nv)−N_(A) _(—) _(RE,nv))/(T_(A) _(—) _(RE,nv)+N_(A) _(—)_(RE,nv))>0.15, preferably >0.20, preferably >0.25, preferably >0.30].

According to another aspect, the invention provides a pair of targetoptical functions of lenses intended for a wearer, wherein thenasal/temporal half-widths of the far-vision zone with respect to afar-vision gaze direction are asymmetric as a function of the wearer'shandedness. Advantageously, the fields are more open (half-widthslarger) on the side of the writing hand.

In one embodiment, for a right-handed wearer, [(T_(P) _(—)_(LE,fv)−N_(P) _(—) _(LE,fv))/(T_(P) _(—) _(LE,fv)+N_(P) _(—)_(LE,fv))≦0 and (T_(P) _(—) _(RE,fv)−T_(P) _(—) _(RE,fv))/(T_(P) _(—)_(RE,fv)+N_(P) _(—) _(RE,fv))≧0] and/or [(T_(A) _(—) _(LE,fv)−N_(A) _(—)_(LE, fv))/(T_(A) _(—) _(LE,fv)+N_(A) _(—) _(LE,fv))≦0 and (T_(A) _(—)_(RE,fv)−N_(A) _(—) _(RE,fv))/(T_(A) _(—) _(RE,fv)+N_(A) _(—)_(RE,fv))≧0].

In one embodiment, for a right-handed wearer, [(T_(P) _(—)_(LE,fv)−N_(P) _(—) _(LE,fv))/(T_(P) _(—) _(LE,fv)+N_(P) _(—)_(LE,fv))<0 and (T_(P) _(—) _(RE,fv)−N_(A) _(—) _(RE,fv))/(T_(P) _(—)_(RE,fv)+N_(P) _(—) _(RE,fv))>0] and/or [(T_(A) _(—) _(LE,fv)−N_(A) _(—)_(LE, fv))/(T_(A) _(—) _(LE,fv)−N_(A) _(—) _(LE,fv))<0 and (T_(A) _(—)_(RE,fv)−N_(A) _(—) _(RE,fv))/(T_(A) _(—) _(RE,fv)+T_(A) _(—)_(RE,fv))>0].

In another embodiment, for a right-handed wearer, [(T_(P) _(—)_(LE,fv)−N_(P) _(—) _(LE,fv))/(T_(P) _(—) _(LE,fv)+N_(P) _(—)_(LE,fv))<−0.15, preferably <−0.20, preferably <−0.25, preferably <−0.30and (T_(P) _(—) _(RE,fv)−N_(P) _(—) _(RE,fv))/(T_(P) _(—) _(RE,fv)+N_(P)_(—) _(RE,fv))>0.15, preferably >0.20, preferably >0.25,preferably >0.30] and/or [(T_(A) _(—) _(LE,fv)−N_(A) _(—)_(LE,fv))/(T_(A) _(—) _(LE,fv)+N_(A) _(—) _(LE,fv))<−0.15, preferably<−0.20, preferably <−0.25, preferably <−0.30 and (T_(A) _(—)_(RE,fv)−N_(A) _(—) _(RE,fv))/(T_(A) _(—) _(RE,fv)+N_(A) _(—)_(RE,fv))>0.15, preferably >0.20, preferably >0.25, preferably >0.30].

In one embodiment, for a left-handed wearer, [(T_(P) _(—) _(LE,fv)−N_(P)_(—) _(LE,fv))/(T_(P) _(—) _(LE,fv)+N_(P) _(—) _(LE,fv))≧0 and (T_(P)_(—) _(RE,fv)−N_(P) _(—) _(RE,fv))/(T_(P) _(—) _(RE,fv)+N_(P) _(—)_(RE,fv))≦0] and/or [(T_(A) _(—) _(LE,fv)−N_(A) _(—) _(LE,fv))/(T_(A)_(—) _(LE, fv)+N_(A) _(—) _(LE,fv))≧0 and (T_(A) _(—) _(RE,fv)−N_(A)_(—) _(RE,fv))/(T_(A) _(—) _(RE,fv)+N_(A) _(—) _(RE,fv))<0].

In one embodiment, for a left-handed wearer, [(T_(P) _(—) _(LE,fv)−N_(P)_(—) _(LE,fv))/(T_(P) _(—) _(LE,fv)+N_(P) _(—) _(LE,fv))>0 and (T_(P)_(—) _(RE,fv)−N_(P) _(—) _(RE,fv))/(T_(P) _(—) _(RE,fv)+N_(P) _(—)_(RE,fv))<0] and/or [(T_(A) _(—) _(LE,fv)−N_(A) _(—) _(LE,fv))/(T_(A)_(—) _(LE, fv)+N_(A) _(—) _(LE,fv))>0 and (T_(A) _(—) _(RE,fv)−N_(A)_(—) _(RE,fv))/(T_(A) _(—) _(RE,fv)+N_(A) _(—) _(RE,fv))<0].

In another embodiment, for a left-handed wearer, [(T_(P) _(—)_(LE,fv)−N_(P) _(—) _(LE,fv))/(T_(P) _(—) _(LE,fv)+N_(P) _(—)_(LE, fv))>0.15, preferably >0.20, preferably >0.25, preferably >0.30and (T_(P) _(—) _(RE,fv)−N_(P) _(—) _(RE, fv))/(T_(P) _(—)_(RE,fv)+N_(P) _(—) _(RE,fv))<−0.15, preferably <−0.20, preferably<−0.25, preferably <−0.30] and/or [(T_(A) _(—) _(LE,fv)−N_(A) _(—)_(LE,fv))/(T_(A) _(—) _(LE,fv)+N_(A) _(—) _(LE,fv))>0.15,preferably >0.20, preferably >0.25, preferably >0.30 and (T_(A) _(—)_(RE,fv)−N_(A) _(—) _(RE,fv))/(T_(A) _(—) _(RE,fv)+N_(A) _(—)_(RE,fv))<−0.15, preferably <−0.20, preferably <−0.25, preferably<−0.30].

Target Optical Function with an Asymmetry of an Optical ParameterBetween Nasal and Temporal Parts as a Function of Handedness

In one aspect, handedness is taken into account in that at least oneoptical parameter of the target optical function is made asymmetricbetween the nasal part and the temporal part of the optical function ofthe lens as a function of the wearer's handedness.

In one embodiment, the target optical function is asymmetric in that atleast one optical parameter between the nasal part and the temporal partof the lens is asymmetric as a function of the wearer's handedness. Saidparameter may be selected from

-   -   any one of central vision optical criteria (CVOC) selected from        the group comprising: power in central vision, astigmatism in        central vision, high order aberration in central vision, acuity        in central vision, prismatic deviation in central vision, ocular        deviation, object visual field in central vision, image visual        field in central vision, magnification in central vision, or a        variation of preceding criteria;    -   any one of peripheral vision optical criteria (PVOC) selected        from the group comprising: power in peripheral vision,        astigmatism in peripheral vision, high order aberration in        peripheral vision, pupil field ray deviation, object visual        field in peripheral vision, image visual field in peripheral        vision, prismatic deviation in peripheral vision, magnification        in peripheral vision, or a variation of preceding criteria;    -   any one of global optical criteria (GOC) selected from the group        comprising: magnification of the eye, temple shift, or a        variation of preceding criteria;    -   any one of surface criteria (SC) selected from the group        comprising: front or back mean curvature, front or back minimum        curvature, front or back maximum curvature, front or back        cylinder axis, front or back cylinder, front or back mean        sphere, front or back maximum sphere, front or back minimum        sphere or a variation of preceding criteria; and/or    -   the maximal value (respectively, minimal value, peak-to-valley        value, maximal gradient value, minimal gradient value, maximal        slope value, minimal slope value, average value) of any one of        the preceding criteria,    -   in one or more useful zones of the lens, including zones for        near-vision, distant-vision, and intermediate-vision.

For example, said optical parameter may be the maximal value(respectively, minimal value, peak-to-valley value, maximal gradientvalue, minimal gradient value, maximal slope value, minimal slope value,average value) of any one of resulting astigmatism, refractive powergradient, mean sphere gradient of the front surface, cylinder of thefront surface, in one or more useful zones of the lens for near-vision,distant-vision, and intermediate-vision.

In a preferred embodiment, said optical parameter asymmetric between thenasal part and the temporal part of the lens is selected from maximalresulting astigmatism, maximal power gradient, mean sphere gradient ofthe front surface, cylinder of the front surface. Advantageously, whenthe optical parameter is maximal resulting astigmatism, reduced blur andreduced image deformation are experienced on the side of the lens mainlyused by the wearer. Further, when the optical parameter is maximal powergradient, the gaze alignment on the target is made easier on the side ofthe lens mainly used by the wearer. The invention thus provides enhancedexperience of handedness and improved visual comfort as a function ofthe wearer's handedness.

In one aspect, the target optical function is asymmetric in that boththe above defined nasal/temporal half-widths and the above defined atleast one optical parameter between the nasal part and the temporal partof the lens are asymmetric as a function of the wearer's handedness.

In one aspect, the target optical function is asymmetric in that atleast one optical parameter between the nasal part and the temporal partof the lens is asymmetric as a function of the wearer's handedness, andsaid optical parameter is maximal resulting astigmatism (MaxAsr),defined respectively on the temporal side (MaxAsrT) and on the nasalside (MaxAsrN) of the lens. In such case, the customization of themaximal resulting astigmatism (peak values) advantageously allows tosoften the design of the lens as a function of the wearer's handedness.For example, for a right-handed wearer, the design may be softened onthe right side, namely softened on the temporal side T of the right-eyedRE lens, and/or on the nasal side N of the left-eye LE lens; whereas fora left-handed wearer, the design may be softened on the left-side.

In one embodiment, the target optical function of a lens intended for aright-handed wearer, is such that MaxAsrT−MaxAsrN>0. The lens ispreferably intended for the left eye of the wearer.

In another embodiment, the target optical function of a lens intendedfor a right-handed wearer, is such that MaxAsrT−MaxAsrN<0. The lens ispreferably intended for the right eye of the wearer.

In another embodiment, the target optical function of a lens intendedfor a left-handed wearer, is such that MaxAsrT−MaxAsrN<0. The lens ispreferably intended for the left eye of the wearer.

In another embodiment, the target optical function of a lens intendedfor a left-handed wearer, is such that MaxAsrT−MaxAsrN>0. The lens ispreferably intended for the right eye of the wearer.

The above target optical functions may be paired (RE/LE).

In one aspect, the target optical function is asymmetric in that maximalresulting astigmatism (MaxAsr) is asymmetric between the nasal part Nand the temporal part T of the lens as a function of the wearer'shandedness, wherein (MaxAsrT)−(MaxAsrN) depends on the value ofprescribed addition.

In one embodiment, the target optical function of a lens intended for aright-handed wearer having a prescribed addition A, is such thatMaxAsrT−MaxAsrN>Max(0.25*A−0.25; 0.25). The lens is preferably intendedfor the left eye of the wearer.

In another embodiment, the target optical function of a lens intendedfor a right-handed wearer having a prescribed addition A, is such thatMaxAsrT−MaxAsrN<−Max(0.25*A−0.25; 0.25). The lens is preferably intendedfor the right eye of the wearer.

In another embodiment, the target optical function of a lens intendedfor a left-handed wearer having a prescribed addition A, is such thatMaxAsrT−MaxAsrN<−Max(0.25*A−0.25; 0.25). The lens is preferably intendedfor the left eye of the wearer.

In another embodiment, the target optical function of a lens intendedfor a left-handed wearer having a prescribed addition A, is such thatMaxAsrT−MaxAsrN>Max(0.25*A−0.25; 0.25). The lens is preferably intendedfor the right eye of the wearer.

The above lenses may be paired so as to form a pair of lenses (RE/LE).

In another aspect, the asymmetry between nasal and temporal sides may bedefined as follows in the context of a pair: for a right-handed wearerhaving a prescribed addition A, MaxAsrT_LE−MaxAsrN_LE>Max(0.25*A−0.25;0.25) and MaxAsrT_RE−MaxAsrN_RE<−Max(0.25*A−0.25; 0.25); whereas forleft-handed wearer having a prescribed addition A,MaxAsrT_LE−MaxAsrN_LE<−Max(0.25*A−0.25; 0.25) andMaxAsrT_RE−MaxAsrN_RE>Max(0.25*A−0.25; 0.25).

In the above embodiments, +/−Max(0.25*A−0.25; 0.25) is expressed indiopters (D) and Max denotes the Maximum Value function between(0.25*A−0.25) and 0.25.

In one aspect, the target optical function is asymmetric in that atleast one optical parameter (π) between the nasal (N) part and thetemporal (T) part of the lens is asymmetric as a function of thewearer's handedness. In one aspect:

Δ1=ABS[(π_(T)−π_(N))/avg(π_(T);π_(N))]>0.15

wherein:

-   -   ABS is absolute value,    -   avg denotes the average value.

Preferably the target optical function is such that Δ1>0.20; Δ1>0.25; orΔ1>0.30.

In some embodiments, π is the maximal value of resulting astigmatismMaxAsr or the maximal value of refractive power gradient.

Method for Determining a Pair of Lenses with an Asymmetry Between Leftand Right Target Optical Functions as a Function of Handedness

The invention also relates to a method for determining a pair ofophthalmic lenses intended to be worn by a wearer, wherein the targetoptical function of each lens is asymmetric in that at least a same oneoptical parameter (π) between the nasal (N) part and the temporal (T)part of each respective target optical function is asymmetric as afunction of the wearer's handedness, and wherein further the asymmetriesare of opposite signs between the eyes. The invention thus provides apair of target optical functions of ophthalmic lenses intended to beworn by a wearer having right eye (RE) and left eye (LE), wherein:

-   -   ABS[(π_(T) _(—) _(RE)−π_(N) _(—) _(RE))/avg(π_(T) _(—)        _(RE);π_(N) _(—) _(RE))]>0.15 (preferably, 0.20, 0.30); and    -   ABS[(π_(T) _(—) _(LE)−π_(N) _(—) _(LE))/avg(π_(T) _(—)        _(LE))]>0.15 (preferably, 0.20, 0.30); and    -   optionnally (πT_(RE) _(—) _(LE)−π_(N) _(—) _(RE))/avg(π_(T) _(—)        _(RE); π_(N) _(—) _(RE)) and (π_(T) _(—) _(LE)−π_(N) _(—)        _(LE))/avg(π_(T) _(—) _(LE); π_(N) _(—) _(LE)) are of opposite        signs.

In such situation, the asymmetry for the right eye is not identical tothe asymmetry for the left eye, thus providing for additional asymmetryat the scale of the full pair of lenses.

In another aspect, the present invention provides a method fordetermining a pair of ophthalmic lenses intended to be worn by a wearerhaving right eye (RE) and left eye (LE), wherein the target opticalfunctions of said pair of lenses are asymmetrical between the LE and theRE as a function of the wearer's handedness. For example, the targetoptical functions are asymmetrical in that for at least one opticalparameter (π) defined on the target optical function of the lensintended for the right eye (π_(RE)) and defined on the target opticalfunction of the lens for the left eye (π_(LE)), the amount π_(RE)−π_(LE)is a function of the wearer's handedness. Advantageously, this enablethe design of a pair of lenses, which (all other things being equal,including prescription data, biometry data, frame data, etc.), wouldyield a lens pair design different for a left-handed wearer and aright-handed wearer. The extent of the differences in design may varyaccording to the degree of handedness. According to one embodiment:

-   -   (π_(RE)−π_(LE))/avg(πL_(RE); π_(LE))=aH+b; and    -   optionally ABS [(π_(RE)−π_(LE))/avg(π_(RE); π_(LE))]>0.15;        wherein    -   ABS is absolute value,    -   avg denotes the average value,    -   a and b are constants,    -   H is a handedness parameter.

(a,b) are constants in that they do not depend on handedness in any way.(a,b) may depend on wearer data other than handedness data, such aswearer prescription data or biometry data. H is a handedness parameterthat solely depends on the wearer's handedness. H may be the handednessvalue as described thereafter and in the examples.

H may be determined according to any handedness determination method asper the present disclosure. The skilled person may determine suitable(a,b) values based upon the present disclosure and common generalknowledge. Preferably, (a,b) are selected so thatΔ2=ABS[(π_(RE)−π_(LE))/avg(π_(RE); π_(LE))]>0.15. Preferably (a,b) areselected so that Δ2>0.20; Δ2>0.25; Δ2>0.30.

Pair of Target Optical Functions of Lenses with Insets Asymmetric as aFunction of Handedness

The present invention provides a pair of target optical functions ofspectacle progressive ophthalmic lenses intended to be worn by a wearerhaving a right eye and a left eye, wherein the respective insets aredifferent as a function of the wearer's handedness. Namely, the inset ofthe lens for the right eye is different from the inset of the lens forthe left eye, as a function of the wearer's handedness.

In one aspect, for a wearer having identical prescription data for theright eye and the left eye:

-   -   For a right-handed wearer: Inset_LE>Inset_RE    -   For a left-handed wearer: Inset_RE>Inset_LE

In another aspect, the inset for each lens (inset_RE_initial andinset_LE_initial) may be first determined without taking into accountwearer handedness. The skilled person is aware of methods fordetermining inset values, for example by ray tracing methods, such asray tracing method with respect to an object in the near-vision in themedian plane. The values for inset_RE_initial and inset_LE_initial maybe determined as a function of the prescription data, and whereapplicable, other parameters, such as in accordance with WO2010034727.

Inset values that take into account handedness may then be determined asfollows: for a right-handed wearer:

-   -   Inset_RE=inset_RE_initial−Delta_inset,    -   Inset_LE=inset_LE_initial+Delta_inset        while for a left-handed wearer:    -   Inset_RE=inset_RE_initial+Delta_inset    -   Inset_LE=inset_LE_initial−Delta_inset,        wherein Delta_inset>0.        Delta_(—) inset may be determined as follows:

Delta_inset=[CRE _(—) L/RD]*DPS

wherein

-   -   DPS=Distance between the sagittal plan and the gazed point in        near vision, positive towards the right side of the individual.    -   CRE_L=distance between the center of rotation of the eye and the        lens; CRE_L is defined for the left eye (CRE_L_LE) and right eye        (CRE_L_RE)    -   RD=reading distance from the center of rotation of the eye.

Delta_(—) inset may also be determined as follows:

Delta_inset=DPS/[1+W/CRE _(—) L−W*P]

wherein

-   -   DPS Distance between the sagittal plan and the gazed point in        near vision, positive towards the right side of the individual.    -   CRE_L=distance between the center of rotation of the eye and the        lens, in meter.    -   W=reading distance from the lens, in meter.    -   P=power of the lens in near vision, in diopter.

For example, where the wearer has identical prescription for both eyes,one may choose Delta_inset=about 1 mm.

Inset values that take into account handedness may be also determined asfollows: inset values can be determined by a calculation, a ray-tracingor any other method, using modified values of the monocularpupillary-distance PD_RE′ and PD_LE′, such as:

-   -   PD_RE′=PD_RE−DPS    -   PD_LE′=PD_LE+DPS        wherein    -   DPS=Distance between the sagittal plan and the gazed point in        near vision, positive towards the right side of the wearer.    -   PD_RE=Monocular pupillary distance of the right eye of the        wearer.    -   PD_LE=Monocular pupillary distance of the left eye of the        wearer.

For example, the inset can be calculated according to:

Inset_(—) RE/[1+W/CRE _(—) L _(—) RE−W*P _(—) RE]

Inset_(—) LE=PD _(—) LE′/[1+W/CRE _(—) L LE−W*P _(—) _(LE])

wherein

-   -   CRE_L_RE=distance between the center of rotation of the right        eye and the lens, in meter.    -   CRE_L_LE=distance between the center of rotation of the left eye        and the lens, in meter.    -   W=reading distance from the lens, in meter.    -   P_RE=power of the right lens in near vision, in diopter.    -   P _(—) _(LE)=power of the left lens in near vision, in diopter.

All the above definitions of Delta_inset are illustrated at FIG. 21,wherein O is the object point gazed in near vision.

Target Optical Function Obtained by Deformation or Asymmetrization, as aFunction of Handedness, of an Intermediate Optical Function

In one aspect, the method of the invention comprises a step (SH) and astep (SL) as defined above, wherein (SL) is a determination step byoptical optimization (OPTIM), and wherein the step (Sb) of defining saidtarget optical function comprises the following steps:

-   -   a step (Sb1) of defining an intermediate optical function, and    -   a step (Sb2) of defining said target optical function by        transforming said intermediate optical function as a function of        the wearer's handedness.

In one embodiment, step (Sb1) is a step of defining an intermediateoptical function, thus including the definition of intermediatepositions, values and shapes of: the near-vision zone, theintermediate-vision zone, the distant-vision zone, the meridian line, asa function of the wearer's prescription data. In which case, step (Sb2)comprises:

-   -   shifting and/or rotating and/or enlarging and/or shearing one or        more of the following:        -   the near-vision zone,        -   the intermediate-vision zone,        -   the distant-vision zone,        -   any useful area of the above zones,        -   the meridian line or portion thereof, of the intermediate            optical function as a function of the wearer's handedness;            and/or    -   asymmetrizing the nasal/temporal field half-widths of one or        more of the following:        -   the near-vision zone with respect to a proximate-vision gaze            direction,        -   the intermediate-vision zone with respect to the meridian            line,        -   the distant-vision zone with respect to a distant-vision            gaze direction, of the intermediate optical function as a            function of the wearer's handedness.

In the above step (Sb2), where applicable:

-   -   shifting may be defined as a shift of the useful zone; for        example, regarding a useful near-vision zone, a shift may be        performed as described in WO2006/027448.    -   shearing may be defined as a design translation as a function of        the height on the lens; shearing may be performed as described        in EP-A-1950601, see in particular FIG. 1c and [0069];    -   the optimization may be such that the target optical function(s)        have variable insets. In particular, the above embodiments in        connection with inset definition as a function of handedness are        contemplated;    -   symmetry in the nasal/temporal field half-widths may be as        defined in all the above embodiments on nasal/temporal        asymmetry.        Target Optical Function with Asymmetry of at Least One Optical        Parameter Between the Nasal Part and the Temporal Part, as a        Function of Wearer Handedness

In one aspect, the method of the invention comprises a step (SH) and astep (SL) as defined above, wherein (SL) is a determination step byoptical optimization (OPTIM), and wherein the step (Sb) of defining saidtarget optical function comprises assymetrizing at least one opticalparameter between the nasal part and the temporal part of theintermediate optical function as a function of the wearer's handedness.

In one embodiment, said optical parameter is selected from

-   -   any one of central vision optical criteria (CVOC) selected from        the group comprising: power in central vision, astigmatism in        central vision, high order aberration in central vision, acuity        in central vision, prismatic deviation in central vision, ocular        deviation, object visual field in central vision, image visual        field in central vision, magnification in central vision;    -   any one of peripheral vision optical criteria (PVOC) selected        from the group comprising: power in peripheral vision,        astigmatism in peripheral vision, high order aberration in        peripheral vision, pupil field ray deviation, object visual        field in peripheral vision, image visual field in peripheral        vision, prismatic deviation in peripheral vision, magnification        in peripheral vision;    -   any one of global optical criteria (GOC) selected from the group        comprising: magnification of the eye, temple shift,    -   any one of surface criteria (SC) selected from the group        comprising: front or back mean curvature, front or back minimum        curvature, front or back maximum curvature, front or back        cylinder axis, front or back cylinder, front or back mean        sphere, front or back maximum sphere, front or back minimum        sphere,        and/or the maximal value (respectively, minimal value,        peak-to-valley value, maximal gradient value, minimal gradient        value, maximal slope value, minimal slope value, average value)        of any one of the preceding criteria,

in one or more useful zones of the lens for near-vision, distant-vision,and intermediate-vision.

Use of Handedness as Design Parameter for an Ophthalmic Lens

The present invention provides the use of a wearer's handednessparameter for the determination of a pair of ophthalmic lenses.

The present invention also provides the use of a handedness-specificergorama in a method for determining an ophthalmic lens as a function ofa wearer's handedness.

Said lenses are preferably spectacle progressive ophthalmic lenses. Thehandedness parameter may be obtained as described below, and in theexamples.

Handedness Determination

According to the invention, the lens wearer's handedness may bedetermined in various ways:

-   -   as the answer of the wearer when asked whether (s)he is        left-handed or right-handed for a writing task/activity;    -   as the answer of the wearer when asked whether (s)he is        left-handed or right-handed for a writing task/activity, in        combination with the answer of the wearer when asked whether        (s)he uses a posture such as hooked writing or regular writing.        “Hooked” writing refers to an arm posture such that the wrist of        the writing hand is bent at an angle, generally approximately a        right angle, between the forearm and the hand. This is opposed        to a “regular” handwriting, where the wrist of the writing hand        is generally not bent, so that the hand and the forearm are        aligned. The answer may then be hooked left (resp. right)-handed        or regular left (resp. right)-handed.    -   as the conclusion from an observation of the wearer (human        external assessment), including observation of the writing hand        and of the above hooked/regular posture feature,    -   as the laterality quotient as determined using the Edinburgh        Inventory, as per Oldfield, R. C. “The assessment and analysis        of handedness: the Edinburgh inventory.” Neuropsychologia.        9(1):97-113. 1971;    -   as the laterality quotient as determined by analogy to the        Edinburgh Inventory and following the same computation        principle, but based on the answers of the wearer to one or more        handedness questions, for example 1-5 or 1-10 questions, which        are distinct/adapted from said Inventory; this would amount to a        Edinburgh-like modified handedness Inventory. Notably, it is        possible to define various such modified inventories: general        inventories, distant-vision tasks inventories,        intermediate-vision tasks inventories, near-vision task        inventories (see example);    -   physical testing and/or measurements such as head/eye tracking,        and/or document tracking and/or hand tracking. A handedness        parameter/value may also be computed as a function of a head/eye        behaviour score. The head/eye behaviour score can be measured        using an apparatus known under the name Visioffice or Vision        Print System, or the head/eye behaviour score can be determined        by eye tracking, such as SMI Eye tracking glasses (SensoMotoric        Instrument), ASL eye tracking glasses (Applied Science        Laboratories), etc.

Independently of the nature of the method used to determine a wearer'shandedness, it is possible to define a handedness value H. Said valuemay be determined according to various methods.

In one embodiment, the wearer is asked a single question, for examplewhich hand s/he uses to perform hand writing. If the answer is “right”,then the handedness is determined as “right-handed” and a handednessvalue H of +100 can be allocated. If the answer is “left”, then thehandedness is determined as “left-handed” and a handedness value H of−100 can be allocated.

In another embodiment, handedness value H may be determined inaccordance with the Edinburgh Inventory. The protocol is as described byOldfield, R. C. “The assessment and analysis of handedness: theEdinburgh inventory.” Neuropsychologia 9(1):97-113 (1971). In accordancewith this method, the subject is asked a series of handedness relatedquestions and is to answer quantitatively. The outcome is a lateralityquotient LQ, which ranges from −100 (very left-handed) to +100 (veryright-handed). Accordingly, a handedness value H can be defined as theLQ value obtained following this method.

In another embodiment, handedness value H may be determined inaccordance with modified Edinburgh inventories. It is possible to followthe same principle of quotient computing as per Oldfield, R. C. “Theassessment and analysis of handedness: the Edinburgh inventory.”Neuropsychologia. 9(1):97-113 (1971), but with modifications regardingthe nature of the questions. In particular, it is possible to defineH=LQ values for distant-vision (respectively intermediate vision,respectively near-vision), by listing questions related to tasks usingdistant-vision (respectively intermediate vision, respectivelynear-vision). For example, near-vision tasks that may be used to definenear-vision LQ may include one or more of write on a piece of paper,dial a number on a desk phone, dial a number on a portable/cell phone,navigate on a touch screen (e-tablet, smart phone), stir contents of apot or a pan, shave or apply makeup. Example of far-vision task: pointtowards a plane in the sky, or any other distant point; bow shooting.Example of intermediate-vision tasks: start up the dishwasher or theoven; reach for an item placed on a high shelf. The subject is providedwith the following questionnaire:

Which hand do you use to perform Left Right Task 1 Task 2 Task 3(etc)

The subject is asked to please indicate his/her preferences in the useof hands in each task by putting “+” in the appropriate column. If thepreference is so strong that one would never try to use the other handunless absolutely forced, one puts “++”. If in any case the subject isindifferent, put “+” in both column. LQ is defined as [(number of “+” in“right” column) (number of “+” in “left” column)/number of “+”] *100.

Computer Program Products

The present invention provides a (non-transitory) computer programproduct comprising one or more stored sequence(s) of instructions thatis accessible to a processor and which, when executed by the processor,causes the processor to carry out the steps of any one of the abovedescribed methods.

The present invention also provides a (non-transitory) computer readablemedium carrying out one or more sequences of instructions of thecomputer program product of the invention.

Methods for Providing or Manufacturing an Ophthalmic Lens

The invention provides a computer-implemented method for providing anophthalmic lens intended to be worn by a wearer, comprising:

-   -   a step of inputting wearer data in a computer system,    -   a step of inputting wearer handedness data in said computer        system,        wherein said computer system is provided with processing means        for outputting, based upon said wearer data and handedness data,        at least one set of data characterizing said ophthalmic lens.

The processing means may advantageously be suitable for performing theabove methods of the invention for determining an ophthalmic lens as afunction of the wearer's handedness.

Further, in said computer-implemented method, the computer system maycomprise a computer program product and/or a computer readable medium asdescribed above.

The invention further provides a method for manufacturing an ophthalmiclens intended to be worn by a wearer, comprising saidcomputer-implemented method of the invention.

The invention is illustrated by the following non-limiting examples.

Example 1 Progressive Lens Designs with Asymmetric Temporal/NasalHalf-Widths in Near Vision (Power and Astigmatism) as a Function ofWearer Handedness

All parameters in Example 1 relate to near-vision, but are not annotatedas such for simplification purposes.

Example 1A Near-Vision Behavior is Handedness-Dependent

Protocol:

The specific near vision task of writing on a sheet of paper is thenconsidered for a group of test individuals. To this end, as illustratedin FIG. 8, a writing zone 40 of a document 42 is considered and definedas the area of the document 42 where the subject is writing. Each personof the group is placed in the condition of writing on the writing zone40. At this time, the projection 44L, 44R of the writing zone 40 in theplane of the left and the right lens is computed, recorded and analyzed.These projections 44L, 44R are also called useful near vision zones orsimply useful zones in the remainder of the description.

Results:

FIG. 9 shows superposition of the useful zones 44L, 44R recorded forright-handed persons who sustained the experience and FIG. 10 showssuperposition of the useful zones 44L, 44R for left-handed persons whosustained the experience.

From these FIGS. 9-10, it can be seen that the useful zones 44L, 44Rgreatly differ between right-handed and left-handed persons.

Besides, there is a high variability of the useful zones amongleft-handed persons, leading to a mean useful zone which is large andsubstantially aligned along an axis parallel to the horizontal axis(α=0°). On the contrary, among right-handed persons, the variability ofthe useful zones is reduced, leading to a mean useful zone which issmaller and substantially inclined relative to the horizontal axis.Table 1 summarizes the useful zones identified.

The useful zones 44L, 44R can thus be exploited based on theirorientation relative to the horizontal axis.

TABLE 1 Left-handed Right-handed Left lens Right lens Left lens Rightlens Minimum angle of −26 −28 7 7 inclination (°) Maximum angle of 52 4954 48 inclination (°) Standard deviation (°) 22 22 12 11 Mean angle ofinclination 7 6 20 19 (°)

Based on the data collected and expressed in Table 1, on average, theright-handed persons incline the document 42 by an angle of about 20°when performing a near vision task such as writing, whereas for theleft-handed persons, the inclination is not significantly different from0°, so the mean inclination angle is considered to be 0°.

Conclusion:

Such a high variability in the orientation of document 42 in writingtasks demonstrates the existence of specific behaviors betweenright-handed and left-handed persons and therefore implies a need toprovide different designs in near vision for right-handed andleft-handed wearers. Particularly, the near vision zone of the lenseshave to be adapted to match in an optimal way the mean projection on therespective lenses of the useful zone swept during a near vision task.

Example 1B Asymmetrizing Lens Nasal/Temporal Half-Widths (Power,Astigmatism) in Near-Vision as a Function of Handedness: Determinationof Useful Vision Zones

The present example provides two different designs of a pair ofprogressive ophthalmic lenses, one specific design for left-handedpersons and one specific design for right-handed persons. This examplerelates to lens design in the near-vision zone with asymmetric featuresfor nasal and temporal near-vision half-widths.

The criteria taken into account in the following are the ratio R_(PL),R_(PR) of the difference over the sum of temporal and nasal half-widthsof refractive power for the left-eye lens and the right-eye lens, andthe ratio R_(AL), R_(AR) of the difference over the sum of temporal andnasal half-widths of module of resulting astigmatism for the left-eyelens and the right-eye lens:

$R_{PL} = \frac{T_{P\_ {LE}} - N_{P\_ {LE}}}{T_{P - {LE}} + N_{P\_ {LE}}}$$R_{PR} = \frac{T_{P\_ {RE}} - N_{P\_ {RE}}}{T_{P - {RE}} + N_{P\_ {RE}}}$$R_{AL} = \frac{T_{A\_ {LE}} - N_{A\_ {LE}}}{T_{A - {LE}} + N_{A\_ {LE}}}$$R_{AR} = \frac{T_{A\_ {RE}} - N_{A\_ {RE}}}{T_{A - {RE}} + N_{A\_ {RE}}}$

For each lens of the pair, at least one criterion is determined based onthe laterality of the wearer, that is to say either the ratio ofrefractive power R_(P) or the ratio of module of resulting astigmatismR_(A) or both.

According to the results summarized in Table 1 above and explained withreference to FIGS. 9 and 10, the chosen criterion is determineddifferently for the left-handed and right-handed persons.

For the left-handed persons, as the inclination relative to thehorizontal axis of the projections of the writing zone 40 on the planeof the left-eye and right-eye lenses is substantially equal to 0°, thedesign for both the left-eye and right-eye lenses is symmetric relativeto the corresponding proximate vision gaze direction (α_(PVL), β_(PVL)),(α_(PVR), β_(PVR)).

This condition is expressed by the fact that, for the left-handedpersons, the ratio of the difference over the sum of temporal and nasalhalf-widths of refractive power is set substantially to 0 for each lensof the pair and/or the ratio of the difference over the sum of temporaland nasal half-widths of module of resulting astigmatism is setsubstantially to 0 for each lens of the pair:

R _(PL) =R _(PR)=0 and/or R _(AL) =R _(AR)=0

These equations result in the fact that, for the left-handed persons,the left and right temporal half-widths of refractive power aresubstantially equal respectively to the left and right nasal half-widthsof refractive power and/or the left and right temporal half-widths ofmodule of resulting astigmatism are substantially equal respectively tothe left and right nasal half-widths of module of resulting astigmatism:

T _(P) _(—) _(LE) =N _(P) _(—) _(LE) and T _(P) _(—) _(RE) =N _(P) _(—)_(RE)

and/or

T _(A) _(—) _(LE) =N _(A) _(—) _(LE) and T _(A) _(—) _(RE) =N _(A) _(—)_(RE)

Table 2 summarizes the values of the criteria of resulting astigmatismR_(AL), R_(AR) for the left-handed persons, for a proximate vision gazedirection where the refractive power reaches P_(FV) plus 85% of theprescribed addition and for a proximate vision gaze direction where therefractive power reaches P_(FV) plus 100% of the prescribed addition.

TABLE 2 P_(αPV, βPV) = P_(αPV, βPV) = Left-handed criteria P_(FV) +85% * A P_(FV) + 100% * A Mean value 0.00 0.00 Tolerance range ±0.12±0.12 Preferred value 0.00 0.00

For the right-handed persons, as the projections of the writing zone 40on the plane of the left-eye and right-eye lenses is inclined by anangle of about 20° relative to the horizontal axis, the design for boththe left-eye and right-eye lenses is dissymmetric relative to thecorresponding proximate vision gaze direction (α_(PVL), β_(PVL)),(α_(PVR), β_(PVR)).

This condition is expressed by the fact that, for the right-handedpersons, the ratio of the difference over the sum of temporal and nasalhalf-widths of refractive power is set to a value greater than 0 for theright-eye lens and the ratio of the difference over the sum of temporaland nasal half-widths of refractive power is set to a value less than 0for the left-eye lens and/or the ratio of the difference over the sum oftemporal and nasal half-widths of module of resulting astigmatism is setto a value greater than 0 for the right-eye lens and the ratio of thedifference over the sum of temporal and nasal half-widths of module ofresulting astigmatism is set to a value less than 0 for the left-eyelens:

R _(PR)>0 and R _(PL)<0

and/or

R _(AR)>0 and R _(AL)<0

These equations result in the fact that, for the right-handed persons,the right temporal half-width of refractive power is greater than theright nasal half-width of refractive power and the left temporalhalf-width of refractive power is less than the left nasal half-width ofrefractive power and/or the right temporal half-width of module ofresulting astigmatism is greater than or equal substantially to theright nasal half-width of module of resulting astigmatism and the lefttemporal half-width of module of resulting astigmatism is less than orequal substantially to the left nasal half-width of module of resultingastigmatism:

T _(P) _(—) _(RE) >N _(P) _(—) _(RE) and T _(P) _(—) _(LE) <N _(P) _(—)_(LE)

and/or

T _(A) _(—) _(RE) >N _(A) _(—) _(RE) and T _(A) _(—) _(LE) <N _(A) _(—)_(LE)

In particular, for the right-handed persons, the sum of the ratio of thedifference over the sum of temporal and nasal half-widths of refractivepower for the right-eye lens and the ratio of the difference over thesum of temporal and nasal half-widths of refractive power for theleft-eye lens is set substantially to 0 and/or the sum of the ratio ofthe difference over the sum of temporal and nasal half-widths of moduleof resulting astigmatism for the right-eye lens and the ratio of thedifference over the sum of temporal and nasal half-widths of module ofresulting astigmatism for the left-eye lens is set substantially to 0:

R _(PR) +R _(PL)=0

and/or

R _(AR) +R _(AL)=0

Table 3 summarizes the values of the criteria of resulting astigmatismR_(AL), R_(AR) for the right-handed persons, for a proximate vision gazedirection where the refractive power reaches P_(FV) plus 85% of theprescribed addition and for a proximate vision gaze direction where therefractive power reaches P_(FV) plus 100% of the prescribed addition.

TABLE 3 P_(αPV, βPV) = P_(αPV, βPV) = Right-handed criteria P_(FV) +85% * A P_(FV) + 100% * A Right-eye lens values >0.12 >0.12 Preferredright-eye lens 0.15 0.20 value Left-eye lens values <−0.12 <−0.12Preferred left-eye lens −0.15 −0.20 value

Therefore, the invention provides two specific designs for a pair ofprogressive ophthalmic lenses according to the laterality of the wearer.

According to another aspect, the invention provides a process fordetermining a pair of personalized progressive ophthalmic lensesintended for a particular wearer.

This process differs from the above process relating to aleft-handed/right-handed segmentation in that the useful near visionzones 44L, 44R of this wearer and the inclination of the useful nearvision zones 44L, 44R are measured and the criteria are determined basedon the measured inclination.

Consequently, the obtained design is adapted to this particular wearerand not to the average of the left-handed or right-handed persons.

Obviously, other near vision tasks such as reading, writing on acomputer, using a smartphone, etc. could be considered.

According to the invention, the design can be further refined by takinginto account the head/eye behaviour of the wearer. Indeed, whenexecuting a near vision task, some persons rather tend to move theireyes and other persons rather tend to move their head.

The inventors have found that, for an eye mover wearer, the areas of thelenses actually used correspond to the full projections on the lenses ofthe writing zone 40, whereas for a head mover wearer, the areas of thelenses actually used correspond to a fraction of the projections on thelenses of the writing zone 40. A head/eye behaviour score can becalculated and the projection of the writing zone 40 can be weighted bya coefficient which depends on the head/eye behaviour score. Thehead/eye behaviour score can be measured using an apparatus known underthe name Visioffice or Vision Print System, or the head/eye behaviourscore can be determined by eye tracking, such as SMI Eye trackingglasses (SensoMotoric Instrument), ASL eye tracking glasses (AppliedScience Laboratories), etc.

Example 1C Specific Lens Designs

FIGS. 11 to 18 and 19 a to 22 a give optical characteristics of thelenses considered.

FIGS. 11, 13, 15, 17, 19 a and 21 a are refractive power maps. Thevertical and horizontal axes of the maps are the values of the loweringangle α and azimuth angle β of the gaze directions. The isometric curvesindicated on these maps connect gaze directions which correspond to asame refractive power value. The respective refractive power values forthe curves are incremented by 0.25 δ between neighbouring curves, andare indicated on some of these curves.

FIGS. 12, 14, 16, 18, 20 a and 22 a are resulting astigmatism maps. Theaxes of these maps are similar to those of the refractive power maps andthe isometric curves indicated on these maps connect gaze directionswhich correspond to a same resulting astigmatism value. Each of thesemaps also show the meridian line.

On each of these maps, three specific points PV, A and B are considered.

Point PV corresponds to the proximate vision gaze direction which isrelated to the proximate vision control point.

In the examples below, point PV is the point on the front surface of thelens intersecting the gaze direction where the refractive power reachesthe far vision mean power prescribed for that lens plus 100% of theaddition prescribed for that lens.

Point A is located on the temporal side of the lens such that thedistance between point A and point PV corresponds to the temporalhalf-width as defined above.

Point B is located on the nasal side of the lens such that the distancebetween point B and point PV corresponds to the nasal half-width asdefined above.

PAIR1—FIGS. 11 to 14: Right-Handed Wearer, Optimisation for ResultingAstigmatism

A pair PAIR1 of progressive ophthalmic lenses according to the inventionis intended for a right-handed wearer and has been optimized in terms ofresulting astigmatism.

In this case, the power prescription is +0.75 δ in far vision and theprescribed addition is 1.50 δ for both lenses of the pair. Noastigmatism is prescribed for the wearer.

FIGS. 11 and 12 give optical characteristics (refractive power andresulting astigmatism) of the right-eye lens LENS1 of the pair.

FIGS. 13 and 14 give optical characteristics (refractive power andresulting astigmatism) of the left-eye lens LENS2 of the pair.

On FIG. 11:

-   -   Point PV is located at α_(PVR)=28.9° and β_(PVR)=4.9°    -   Point PV is located on the isometric curve corresponding to a        power value:    -   P=0.75+100%*1.5=2.25δ

On FIG. 12:

-   -   point PV is located at α_(PVR)=28.9° and β_(PVR)=4.9°    -   point A is located at α_(AR)=α_(PVR)=28.9° and β_(AR)=−1.4°    -   point B is located at α_(BR)=α_(PVR)=28.9° and β_(BR)=8.4°    -   The isometric curve connecting points A and B correspond to a        resulting astigmatism value:    -   Asr=1.5/4=0.375 δ    -   T_(A) _(—) _(RE)=6.3° and N_(A) _(—) _(RE)=3.5°    -   Then R_(AR)=0.28

On FIG. 13:

-   -   Point PV is located at α_(PVL)=29.0° and β_(PVL)=−4.9°    -   Point PV is located on the isometric curve corresponding to a        power value:    -   P=0.75+100%*1.5=2.25 6

On FIG. 14:

-   -   point PV is located at α_(PVL)=29.0° and β_(PVL)=−4.9°    -   point A is located at α_(Al)=α_(PVL)=29.0° and β_(AL)=−1.2°    -   point B is located at α_(BL)=α_(PVL)=29.0° and β_(BL)=−11.3°    -   The isometric curve connecting points A and B correspond to a        resulting astigmatism value:    -   Asr=−1.5/4 0.375 δ    -   T_(A) _(—) _(LE)=3.7° and N_(A) _(—) _(LE)=6.4°    -   Then R_(AL)=−0.27

This pair PAIR1 is intended for a right-handed person. The resultingastigmatism ratios are such that:

R _(AR)≧0 and R _(AL)≦0

The ratios are further such that R_(AR)+R_(AL) equals substantially to 0taking into account the tolerance range (R_(AR)+R_(AL)=0.01)

This pair of lenses thus provides optimal comfort to a right-handedwearer by providing a dissymmetric design in useful zones when thewearer performs near vision tasks.

PAIR 2—FIGS. 15 to 18: Left-Handed Wearer, Optimisation for ResultingAstigmatism

Example 2 corresponds to a pair PAIR2 of progressive ophthalmic lensesaccording to the invention intended for a left-handed wearer and whichhas been optimized in terms of resulting astigmatism.

In this case, the power prescription is +0.75 δ in far vision and theprescribed addition is 1.50 δ for both lenses of the pair. Noastigmatism is prescribed for the wearer.

FIGS. 15 and 16 give optical characteristics (refractive power andmodule of resulting astigmatism) of the right-eye lens LENS3 of thepair.

FIGS. 17 and 18 give optical characteristics (refractive power andmodule of resulting astigmatism) of the left-eye lens LENS4 of the pair.

On FIG. 15:

-   -   Point PV is located at α_(PVR)=29.1° and β_(PVR)=5.0°    -   Point PV is located on the isometric curve corresponding to a        power value:    -   P=0.75+100%*1.5=2.25 δ

On FIG. 16:

-   -   Point PV is located at α_(PVR)=29.1° and β_(PVR)=5.0°    -   Point A is located at α_(AR)=α_(PVR)=29.1° and β_(AR)=−0.1°    -   Point B is located at α_(RR)=α_(PVR)=29.1° and β_(BR)=10.1°    -   The isometric curve connecting points A and B correspond to a        resulting astigmatism value:    -   Asr=1.5/4=0.375 δ    -   T_(A) _(—) _(RE)=5.1° and N_(A) _(—) _(RE) 5.1°    -   Then R_(AR)=0.00

On FIG. 17:

-   -   Point PV is located at α_(PVL)=29.1° and β_(PVL)=−5.0°    -   Point PV is located on the isometric curve corresponding to a        power value:    -   P=0.75+100%*1.5=2.25 δ

On FIG. 18:

-   -   point PV is located at α_(PVL)=29.1° and β_(PVL)=−5.0°    -   point A is located at α_(BL)=α_(PVL)=29.1° and β_(AL)=0.1°    -   point B is located at α_(BL)=α_(PVL)=29.1° and β_(BL)=−10.1°    -   The isometric curve connecting points A and B correspond to a        resulting astigmatism value:    -   Asr=1.5/4=0.375 δ    -   T_(A) _(—) _(LE)=5.1° and N_(A) _(—) _(LE)=5.1°    -   Then R_(AL), =0.00

This pair PAIR2 is intended for a left-handed person. The resultingastigmatism ratios are such that:

R _(AL) =R _(AR)=0

This pair of lenses thus provides optimal comfort to a left-handedwearer by providing a symmetric design in useful zones when the wearerperforms near vision tasks.

PAIR 3—FIGS. 19 a to 22 a: Left-Handed Wearer

Example 3 corresponds to a pair PAIR3 of progressive ophthalmic lensesaccording to the invention intended for a left-handed wearer and whichhas been optimized in terms of resulting astigmatism.

In this case, the power prescription is +0.75 δ in far vision and theprescribed addition is 1.50 δ for both lenses of the pair. Noastigmatism is prescribed for the wearer.

FIGS. 19 a and 20 a give optical characteristics (refractive power andresulting astigmatism) of the right-eye lens LENS1 of the pair PAIR3.

FIGS. 21 a and 22 a give optical characteristics (refractive power andresulting astigmatism) of the left-eye lens LENS2 of the pair PAIR3.

On FIG. 19 a:

-   -   Point PV is located at α_(PVR)=29.0° and β_(PVR)=5.0°    -   Point PV is located on the isometric curve corresponding to a        power value:    -   P=0.75+100%*1.5=2.25 6

On FIG. 20 a:

-   -   point PV is located at α_(PVR)=29.0° and β_(PVR)=5.0°    -   point A is located at α_(AR)=α_(PVR)=29.0° and β_(AR)=1.3°    -   point B is located at α_(BR)=α_(PVR)=29.0° and β_(BR)=11.4°    -   The isometric curve connecting points A and B correspond to a        resulting astigmatism value:    -   Asr=1.5/4=0.375 6    -   T_(A) _(—) _(RE)=3.7° and N_(A) _(—) _(RE)=6.4°    -   Then R_(AR)=−0.27

On FIG. 21 a:

-   -   Point PV is located at α_(PVL)=28.9° and β_(PVL)=−4.9°    -   Point PV is located on the isometric curve corresponding to a        power value:    -   P=0.75+100%*1.5=2.25 δ

On FIG. 22 a:

-   -   point PV is located at α_(PVL)=28.9° and β_(PVL)=−4.9°    -   point A is located at α_(Al)=α_(PVL)=28.9° and β_(AL)=1.4°    -   point B is located at α_(BL)=α_(PVL)=28.9° and β_(BL)=−8.4°    -   The isometric curve connecting points A and B correspond to a        resulting astigmatism value:    -   Asr=1.5/4=0.375 δ    -   T_(A) _(—) _(LE)=6.3° and N_(A) _(—) _(LE)=3.5°    -   Then R_(AL)=0.28

This pair PAIR3 is intended for a left-handed person. Indeed, theresulting astigmatism ratios are such that:

R _(AR)≦0 and R _(AL)≧0

The ratios are further such that R_(AR)+R_(AL) equals substantially to 0taking into account the tolerance range (R_(AR)+R_(AL)=0.01)

The pair PAIR 3 thus provides optimal comfort to a left-handed wearer byproviding a dissymmetric design in useful zones when the wearer performsnear vision tasks.

Example 2 Progressive Lens Designs with Asymmetric Temporal/NasalHalf-Widths in Far Vision (Power and Astigmatism) as a Function ofWearer Handedness

All parameters in example 2 relate to far vision, but are not annotatedas such for simplification purposes. By analogy to example 1,progressive lens designs are provided with asymmetries with respect tohalf-widths for far vision, as a function of the wearer's handedness:

For a Right-Handed Wearer:

(T _(P) _(—) _(LE) −N _(P) _(—) _(LE))/(T _(P) _(—) _(LE) +N _(P) _(—)_(LE))≦0 and (T _(P) _(—) _(RE) −N _(P) _(—) _(RE))/(T _(P) _(—) _(RE)+N _(P) _(—) _(RE))≧0

and/or

(T _(A) _(—) _(LE) −N _(A) _(—) _(LE))/(T _(A) _(—) _(LE) +N _(A) _(—)_(LE))≦0 and (T _(A) _(—) _(RE) −N _(A) _(—) _(RE))/(T _(A) _(—) _(RE)+N _(A) _(—) _(RE))≧0

For a Left-Handed Wearer:

(T_(P) _(—) _(LE)−N_(P) _(—) _(LE))/(T_(P) _(—) _(LE)+N_(P) _(—)_(LE))≧0 and (T_(P) _(—) _(RE)−N_(P) _(—) _(RE))/(T_(P) _(—) _(RE)+N_(P)_(—) _(RE))≦0

and/or

(T _(A) _(—) _(LE) −N _(A) _(—) _(LE))/(T _(A) _(—) _(LE) +N _(A) _(—)_(LE))≧0 and (T _(A) _(—) _(RE)−N_(A) _(—) _(RE))/(T _(A) _(—) _(RE) +N_(A) _(—) _(RE))≦0

By way of illustration:

For a Right-Handed Wearer:

(T _(P) _(—) _(LE) −N _(P) _(—) _(LE))/(T _(P) _(—) _(LE) +N _(P) _(—)_(LE))<−0.18 and (T _(P) _(—) _(RE) −N _(P) _(—) _(RE))/(T _(P) _(—)_(RE) +N _(P) _(—) _(RE))>0.18

and/or

(T _(A) _(—) _(LE) −N _(A) _(—) _(LE))/(T _(A) _(—) _(LE) +N _(A) _(—)_(LE))<−0.25 and (T _(A) _(—) _(RE) −N _(A) _(—) _(RE))/(T _(A) _(—)_(RE) +N _(A) _(—) _(RE))>0.25

For a Left-Handed Wearer:

(T _(P) _(—) _(LE) −N _(P) _(—) _(LE))/(T _(P) _(—) _(LE) +N _(P) _(—)_(LE))>0.18 and (T _(P) _(—) _(RE) −N _(P) _(—) _(RE))/(T _(P) _(—)_(RE) +N _(P) _(—) _(RE))<−0.18

and/or

(T _(A) _(—) _(LE)−N_(A) _(—) _(LE))/(T _(A) _(—) _(LE) +N _(A) _(—)_(LE))>0.25 and (T _(A) _(—) _(RE) −N _(A) _(—) _(RE) +N _(A) _(—)_(RE))<−0.25

Advantageously according to the invention, the fields are more opentowards the side of the hand used for far vision tasks, such as pointingtowards an object situated at a distance.

Example 3 Progressive Lens Designs with Asymmetric Astigmatism Peaks(Maxima) as a Function of the Wearer's Handedness

Nasal (resp. temporal) astigmatism peak value MaxAsrN (resp. MaxAsrT) isdefined as the maximal value of resulting astigmatism in the nasal(resp. temporal) side of the lens. The softness of the design may becharacterized by the astigmatism peak, can be customized as a functionof the wearer's handedness. The design may be softened on the side ofthe writing hand (LE, left eye; RE: right eye):

For a Right-Handed Wearer:

-   -   MaxAsrT_LE−MaxAsrN_LE>0 and MaxAsrT_RE−MaxAsrN_RE<0

For a Left-Handed Wearer:

-   -   MaxAsrT_LE−MaxAsrN_LE<0 and MaxAsrT_RE−MaxAsrN_RE>0.

Optionally, the designs may further take into account the value A ofprescribed addition. Advantageously, this results in less blur on thesides of the lens which are mainly used. Further, the head is morerotated towards the side of the hand, so that if the design is softer,then there is advantageously less visual distortion on this side.

-   -   For a right-handed wearer:    -   MaxAsrT_LE−MaxAsrN_LE>Max(0.25*A−0.25; 0.25) and    -   MaxAsrT_RE−MaxAsrN_RE<−Max(0.25*A−0.25; 0.25);    -   For a left-handed wearer:    -   MaxAsrT_LE−MaxAsrN_LE<−Max(0.25*A−0.25; 0.25) and    -   MaxAsrT_RE−MaxAsrN_RE>Max(0.25*A−0.25; 0.25).

By way of example:

-   -   For a right-handed wearer:    -   MaxAsrT_LE−MaxAsrN_LE>0.50 and    -   MaxAsrT_RE−MaxAsrN_RE<−0.50;    -   For a left-handed wearer:    -   MaxAsrT_LE−MaxAsrN_LE<−0.5 and    -   MaxAsrT_RE−MaxAsrN_RE>0.50.

Example 4 Handedness Determination

The following illustrates determination of handedness followingdifferent methods.

Single Question

A wearer is asked which hand s/he uses to perform hand writing.

-   -   If the answer is “right”, then the handedness is determined as        “right-handed” and a handedness value of +100 can be allocated.    -   If the answer is “left”, then the handedness is determined as        “left-handed” and a handedness value of −100 can be allocated.

Edinburgh Inventory

The protocol is as described by Oldfield, R. C. “The assessment andanalysis of handedness: the Edinburgh inventory.” Neuropsychologia9(1):97-113 (1971).

In accordance with the method, the subject is asked a series ofhandedness related questions and is to answer quantitatively. Theoutcome is a laterality quotient LQ, which ranges from −100 (veryleft-handed) to +100 (very right-handed).

Accordingly, a handedness value H can be defined as the LQ valueobtained following this method.

Modified Edinburgh Inventories

It is possible to follow the same principle of quotient computing as perOldfield, R. C. “The assessment and analysis of handedness: theEdinburgh inventory.” Neuropsychologia. 9(1):97-113 (1971), but withmodifications regarding the nature of the questions. In particular, itis possible to define H=LQ values for distant-vision (respectivelyintermediate vision, respectively near-vision), by listing questionsrelated to tasks using distant-vision (respectively intermediate vision,respectively near-vision). For example, near-vision tasks that may beused to define near-vision LQ may include one or more of:

-   -   write on a piece of paper,    -   dial a number on a desk phone,    -   dial a number on a portable/cell phone,    -   navigate on a touch screen (vending machine, e-tablet, smart        phone),    -   stir contents of a pot or a pan,    -   shave or apply makeup.

Example of far-vision task: point towards a plane in the sky, or anyother distant point; bow shooting.

Example of intermediate-vision tasks: start up the dishwasher or theoven; reach for an item placed on a high shelf.

Computation Principle in Modified Edinburgh Inventories

The subject is provided with the following questionnaire:

Which hand do you use to perform Left Right Task 1 Task 2 Task 3(etc)

The subject is asked to please indicate his/her preferences in the useof hands in each task by putting “+” in the appropriate column. If thepreference is so strong that one would never try to use the other handunless absolutely forced, one puts “++”. If in any case the subject isindifferent, put “+” in both column.

H=LQ is defined as [(number of “+” in right column)−(number of “+” inleft column)/number of “+”]*100.

Example of Computation for Modified Edinburgh Inventories in DifferentVision Zones

Vision zone Which hand do you use to perform Left Right distant Pointtowards a plane in the sky +LQ (distant vision)=[(0−1)/1]*100=−100

Vision zone Which hand do you use to perform Left Right intermediateReach for an item placed on a high shelf + + Start-up dishwasher or oven++LQ (intermediate vision)=[(3−1)/4]*100=+50

Vision zone Which hand do you use to perform Left Right near Hand write++ Use touch screen of smart phone + Stir content of pot ++LQ (near vision)=[(5−0)/5]*100=+100

Advantageously, the use of the various laterality quotients as ahandedness factor according to the invention allows to defineindividually the level of asymmetry for each of the near-vision,far-vision and intermediate-vision zones, on each of the lenses.

Example 5 Pair of Lenses with Asymmetric Insets as a Function ofHandedness

The inset for each lens (inset_RE_initial and inset_LE_initial) is firstdetermined without taking into account wearer handedness. The values forinset_RE_initial and inset_LE_initial are determined as a function ofthe prescription data, and where applicable, other parameters, such asin accordance with WO2010034727.

Inset values that take into account handedness may then be determined asfollows: for a right-handed wearer:

-   -   inset RE=inset_RE_initial−Delta_inset,    -   inset LE=inset_LE_initial+Delta_inset        while for a left-handed wearer:    -   inset_RE=inset_RE_initial+Delta_inset    -   inset_LE=inset_LE_initial−Delta_inset,        wherein:    -   SPD=Distance between the sagittal plan and the gazed point in        near vision=30 mm    -   CRE_L=distance between the center of rotation of the eye and the        lens=25.5 mm    -   RD=reading distance=400 mm

Delta_inset=CRE_L/DL*DPS=1.9 mm. Example 6 Progressive Lenses ObtainableAccording to the Invention

FIG. 22 shows resulting astigmatism maps of progressive lensesobtainable according to the invention. The lenses are designed for awearer having identical prescription data for the two eyes (+4 Add 2).

FIG. 22 shows resulting astigmatism maps of progressive lenses of theinvention.

The lenses are designed for near-vision for a right-handed wearer havingidentical prescription data for the two eyes (+4 Add 2). The maps areobtained using ray-tracing as described above, and show values forresulting astigmatism as a function of the gaze direction, wherein thelenses are positioned in average wearing conditions.

On each lens, the right-hand side of the wearer is favoured with respectto maximal value of resulting astigmatism (Max Asr):

On the right-eye lens, Max Asr (temporal)<Max Asr (nasal), whereas onthe left-eye lens, Max Asr (nasal)<Max Asr (temporal).

Example 7 Definition of an Ergorama for a Right-Handed Wearer

FIG. 20 shows an example of an ergorama designed for a right-handedwearer.

The ergorama is defined in the Cyclopean system of referencecoordinates. This binocular system of coordinates is centered on thecenter of rotation of a virtual “eye” (ERC_C), the Cyclopean eye,situated for instance in the middle of the segment defined by therespective centers of rotation of the two eyes of the wearer (ERC_L,ERC_R). The Cyclopean system of coordinates is illustrated by FIG. 19,with a gaze direction (αw,βw) corresponding to object W.

FIG. 20 is the proximity graph, i.e. it represents the inverse of thedistance (in m⁻¹) as a function of the gaze direction. Advantageouslyaccording to the invention, proximity is slightly smaller on theright-side of the Cyclopean system of coordinates (βw>0) in near-vision.Indeed, during a writing task, for a right-handed wearer, the distanceis greater on the right side than on the left side.

1. An ophthalmic lens supply system for providing an ophthalmic lensadapted to be worn by a wearer, comprising: first processing meanssuitable for placing an order of an ophthalmic lens, wherein said firstprocessing means are located at a lens ordering side and comprise:inputting means suitable for the input of wearer data, inputting meanssuitable for the input of wearer handedness data; second processingmeans suitable for providing lens data based upon wearer data and wearerhandedness data, wherein said second processing means are located at alens determination side and comprise outputting means suitable foroutputting said lens data; and first transmission means suitable fortransmitting said wearer data and wearer handedness data, from saidfirst processing means to said second processing means.
 2. Theophthalmic lens supply system according to claim 1, further comprising:manufacturing means suitable for manufacturing an ophthalmic lens basedupon lens data, wherein said manufacturing means are located at a lensmanufacturing side, and second transmission means suitable fortransmitting said lens data from said second processing means to saidmanufacturing means.
 3. The ophthalmic lens supply system according toclaim 1, wherein the second processing means comprise a memory.
 4. Acomputer-implemented method for the determination of an ophthalmic lensintended to be worn by a wearer, said method comprising: a step ofproviding data on the wearers handedness, and a step of determining theophthalmic lens, wherein the step for determining the ophthalmic lenstakes into account the wearer's handedness.
 5. The computer-implementedmethod according to claim 4, wherein said step of determining theophthalmic lens is: a step for selecting a lens from a range ofophthalmic lenses designed according to wearer handedness, or acalculation step, or a determination step by optical optimization. 6.The computer-implemented method according to claim 5, wherein saidwearer was issued a prescription containing prescription data, andwherein said step for determining the ophthalmic lens is a determinationstep by optical optimization that comprises: a step of selecting anergorama, a step of defining a target optical function for said lens asa function of the wearer's prescription data, a step of carrying outoptimization by: selecting an initial lens, defining a current lens, acurrent optical function being defined for the current lens, the currentlens being initially defined as the initial lens, carrying out anoptical optimization for minimizing the difference between the currentoptical function and the target optical function, for example with acost or a merit function, wherein said ergorama is handedness-dependentand optionally activity-dependent, and/or wherein the target opticalfunction is designed as a function of the wearer's handedness.
 7. Thecomputer-implemented method according to claim 6, wherein the step ofdefining said target optical function comprises a step of asymmetrizingthe nasal/temporal field half-widths of one or more of the following:the near-vision zone with respect to a proximate-vision gaze direction,the intermediate-vision zone with respect to the meridian line, thedistant-vision zone with respect to a distant-vision gaze direction, ofthe target optical function as a function of the wearer's handedness,and/or asymmetrizing at least one optical parameter of the targetoptical function between the nasal part and the temporal part of thelens as a function of the wearers handedness, wherein said opticalparameter is selected from any one of central vision optical criteriaselected from the group comprising: power in central vision, astigmatismin central vision, high order aberration in central vision, acuity incentral vision, prismatic deviation in central vision, ocular deviation,object visual field in central vision, image visual field in centralvision, magnification in central vision; any one of peripheral visionoptical criteria selected from the group comprising: power in peripheralvision, astigmatism in peripheral vision, high order aberration inperipheral vision, pupil field ray deviation, object visual field inperipheral vision, image visual field in peripheral vision, prismaticdeviation in peripheral vision, magnification in peripheral vision; anyone of global optical criteria selected from the group comprising:magnification of the eye, temple shift, any one of surface criteriaselected from the group comprising: front or back mean curvature, frontor back minimum curvature, front or back maximum curvature, front orback cylinder axis, front or, back cylinder, front or back mean sphere,front or back maximum sphere, front or back minimum sphere, and/or themaximal value (respectively, minimal value, peak-to-valley value,maximal gradient value, minimal gradient value, maximal slope value,minimal slope value, average value) of any one of the precedingcriteria, in one or more useful zones of the lens for near-vision,distant-vision, and intermediate-vision.
 8. The computer-implementedmethod according to claim 6, wherein the step of defining said targetoptical function comprises: a step of defining an intermediate opticalfunction, thus including the definition of intermediate positions,values and shapes of: the near-vision zone, the intermediate-visionzone, the distant-vision zone, the meridian line, as a function of thewearer's prescription data, and a step of defining said target opticalfunction by transforming said intermediate optical function as afunction of the wearer's handedness, wherein said target opticalfunction defining step comprises: shifting and/or rotating and/orenlarging and/or shearing one or more of the following: the near-visionzone, the intermediate-vision zone, the distant-vision zone, any usefularea of the above zones, the meridian line or portion thereof, of theintermediate optical function as a function of the wearer's handedness;and/or asymmetrizing the nasal/temporal field half-widths of one or moreof the following: the near-vision zone with respect to aproximate-vision gaze, direction, the intermediate-vision zone withrespect to the meridian line, the distant-vision zone with respect to adistant-vision gaze direction, of the intermediate optical function as afunction of the wearer's handedness, and/or assymetrizing at least oneoptical parameter between the nasal part and the temporal part of theintermediate optical function as a function of the wearer's handedness,wherein said optical parameter is selected from any one of centralvision optical criteria selected from the group comprising: power incentral vision, astigmatism in central vision, high order aberration incentral vision, acuity in central vision, prismatic deviation in centralvision, ocular deviation, object visual field in central vision, imagevisual field in central vision, magnification in central vision; any oneof peripheral vision optical criteria selected from the groupcomprising: power in peripheral vision, astigmatism in peripheralvision, high order aberration in peripheral vision, pupil field raydeviation, object visual field in peripheral vision, image visual fieldin peripheral vision, prismatic deviation in peripheral vision,magnification in peripheral vision; any one of global optical criteriaselected from the group comprising: magnification of the eye, templeshift, any one of surface criteria selected from the group comprising:front or back mean curvature, front or back minimum curvature, front orback maximum curvature, front or back cylinder axis, front or backcylinder, front or back mean sphere, front or back maximum sphere, frontor back minimum sphere, and/or the maximal value (respectively, minimalvalue, peak-to-valley value, maximal gradient value, minimal gradientvalue, maximal slope value, minimal slope value, average value) of anyone of the preceding criteria, in one or more useful zones of the lensfor near-vision, distant-vision, and intermediate-vision.
 9. (canceled)10. The ophthalmic lens supply system according to claim 1, wherein thewearers handedness is/was previously determined by: the answer of thewearer when asked whether (s)he is left-handed or right-handed for agiven activity such as writing, optionally in combination with theanswer of the wearer when asked whether (s)he uses a posture such ashooked writing or regular writing, the laterality quotient as determinedusing the Edinburgh Inventory or the answer of the wearer when asked oneor more handedness questions, e.g. selected from said Inventory,physical testing and/or measurements such as head/eye tracking.
 11. Anon-transitory computer program product comprising one or more storedsequence(s) of instructions that is accessible to a processor and which,when executed by the processor, causes the processor to carry out thesteps of the method according to claim
 4. 12. A non-transitory computerreadable medium carrying out one or more sequences of instructions ofthe computer program product according to claim
 11. 13. Acomputer-implemented method for providing an ophthalmic lens adapted tobe fitted into a frame and worn by a wearer, comprising: a step ofinputting wearer data in a computer system, a step of inputting wearerhandedness data in said computer system, wherein said computer system isprovided with processing means for outputting, based upon saidprescription data and handedness data, at least one set of datacharacterizing said ophthalmic lens.
 14. (canceled)
 15. A method formanufacturing an ophthalmic lens intended to be worn by a wearer,comprising the computer-implemented method of claim
 14. 16. The methodaccording to claim 4, wherein the wearer's handedness is/was previouslydetermined by: the answer of the wearer when asked whether (s)he isleft-handed or right-handed for a given activity such as writing,optionally in combination with the answer of the wearer when askedwhether (s)he uses a posture such as hooked writing or regular writing,the laterality quotient as determined using the Edinburgh Inventory orthe answer of the wearer when asked one or more handedness questions,e.g. selected from said Inventory, physical testing and/or measurementssuch as head/eye tracking.